WEBVTT

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>> Welcome to the Cypress
College Math Review

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on fractions, decimals,
and percentages.

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Objective one, convert
between fractions and decimals.

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Fractions and decimals are
just two different ways

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of writing the same numbers.

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When we see 0.7, most
people do call it that,

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0.7, or zero point seven.

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But that's not technically
correct.

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The correct way to say the
number is seven-tenths.

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This is the tenths place.

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So seven-tenths.

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Now close your eyes.

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What do you picture when
you say seven-tenths?

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Yeah, seven over 10.

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That's what most people see.

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Seven over 10.

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So if you simply say
a decimal number,

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the technically correct way,

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then you can easily convert
it to fractional form.

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I'm not suggesting that
you should always read 0.7

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as seven-tenths, just when you
want to convert it to a decimal.

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4.1, so that's four
and one-tenth.

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So as a fraction, one-tenth.

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Four and one-tenth.

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This is the hundredths place,

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so this would be read the
technically correct way

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as 36-hundredths.

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So as a fraction, that's
36 over 100, 36-hundredths.

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Yes, it still needs
to be simplified,

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but at least we have
it in fractional form.

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Now to change fractions into
decimals, the other way around,

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we divide the denominator
into the numerator.

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Yes, the bottom into the top.

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To review, to change
decimals into fractions,

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say it the technically
correct way.

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And to change fractions
into decimals,

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divide the bottom into the top.

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Example. Fill in the
following chart converting

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between fraction
and decimal numbers.

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Four-fifths.

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We divide five into four.

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Now five does not go into four,
so we put the decimal point

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in both places and add a zero.

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Five does go into
40 eight times.

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There's no remainder,
so we're done.

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Four-fifths is equal
to eight-tenths, 0.8.

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So we've changed the
fraction into a decimal.

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Now for four and two-thirds.

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Our answer will be
four point something,

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so it's the two-thirds that we
have to change into a decimal.

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Let's divide three into two.

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Now three does not go into two,

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so we put down the
decimal points and a zero.

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Three goes into 20 six times,
and the remainder is two.

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Tack on another zero.

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Three goes into 20 six times,
leaving a remainder of two.

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This process will
continue forever.

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So we have 0.666, and
let's just round that off

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to two decimal places.

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Let's call it 0.67.

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Therefore, four and
two-thirds is equal to four

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and 67-hundredths,
or more simply 4.67.

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Now let's change
5.2 into a fraction.

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Oh, wait a minute.

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We said it wrong.

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Let's not say it that way.

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Five and two-tenths.

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Close your eyes.

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Two-tenths, that's two over 10.

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So we have five and two-tenths.

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Now we need to reduce
two-tenths to one-fifth.

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So five and two-tenths, or 5.2
is equal to five and one-fifth.

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We've changed this decimal
number into a mixed number.

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But that is a fraction.

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Next one, 0.85.

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Don't say it that way.

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This is a hundredths
place, so 85-hundredths.

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If you close your eyes,

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85-hundredths, that's
85 over 100.

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Now let's reduce that.

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What goes into both?

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Five. Five goes into
85 17 times.

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And five goes into 100 20 times.

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So this reduces to 17 over 20.

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So 85-hundredths or 0.85
is equal to 17-twentieths.

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Pause the video and
try these problems.

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Restart the video
when you're finished.

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Objective two.

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Conversion between decimals
or fractions and percents.

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The word per cent
means parts of 100.

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This means that percent can
be considered to be a fraction

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with a denominator of 100.

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Example, write 53% as a
fraction and as a decimal.

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53% means 53-hundredths.

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Close your eyes again.

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53-hundredths.

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You've already got it
in a fractional form.

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53 on top with 100
on the bottom.

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We have our fraction.

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Now let's change
it into a decimal.

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Recall that when
you divide by 10,

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you move the decimal
place to the left once.

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If you divide by 100, you
move the decimal place

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to the left twice.

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53 divided by 100
then, would be 0.53.

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Once again, if you
say it correctly,

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you won't know whether you're
referring to the fractional

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or the decimal form
of the number.

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53-hundredths.

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So 53% equals 53-hundredths or
as a decimal, 53-hundredths.

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When the denominator
of a fraction is 100,

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it's pretty simple to
change between the forms.

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So in the fraction we
have three-hundredths.

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So three-hundredths is
three-hundredths as a decimal.

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There we go.

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We're good.

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0.03. As a percent, well,
since percent means out of 100,

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three-hundredths, that's 3%.

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Decimals. 0.67.

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So that's 67-hundredths.

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As a fraction, 67-hundredths.

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As a percent, 67%.

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All right.

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We've got 49%.

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So percent means out of
100, so 49-hundredths.

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As a fraction, 49 over 100.

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As a decimal, 49-hundredths
or 0.49.

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100%. So that's 100 over
100, which reduces to one.

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So as either a fraction
or a decimal, 100% is one.

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We know that the following
are equivalent, but how is it

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that we convert between
fractions

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and decimals and percents?

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So 53% equals 53-hundredths as
either a fraction or a decimal.

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53-hundredths.

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So it looks like we
need to divide by 100.

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So to change from a percent
into either a fraction

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or a decimal, we divide by 100.

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And then we leave off
the percent symbol.

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To change from a fraction
or a decimal into a percent,

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then we must do the opposite
operation and multiply by 100.

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And then, of course, we
write the percent symbol.

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So 53-hundredths times 100.

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Now write the percent symbol.

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This equals 53%.

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53-hundredths times 100,

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write the percent
symbol, this equals 53%.

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Example. Change 4.2 into
a fraction and a percent.

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Well, first of all,
let's say it correctly.

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Four and two-tenths.

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So four and then a
fraction of two over 10.

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Now two-tenths reduces
to one-fifth,

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so we have four and one-fifth.

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There we go.

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We have it as a mixed number,
and that's what we meant

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by changing it into a fraction.

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Now let's change
it into a percent.

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So to change it to a percent,
we need to multiply by 100

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and write the percent symbol.

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Multiply by 100 and
what does that do?

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That moves the decimal
two places to the right.

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So we have 420%.

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Example. Change one-third
into a decimal and a percent.

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Well, let's first
change it into a decimal.

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So we need to divide the
numerator by the denominator.

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So divide one by three.

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So three doesn't go into one,

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so we put down the decimal
places, we put down the zero.

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Three goes into 10 three
times, that's nine,

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leaving one left over.

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Ah, we're going to get
another repeating decimal.

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So we get 0.33333.

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Let's just round that to 0.33.

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We'll call that our
decimal form.

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It's an approximation,
but that's fine.

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Now, for the percent.

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We could take the decimal
form and multiply by 100,

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which means to move the decimal
to the right two places, 33%.

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Now since we rounded off,

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technically it should be
33 and a third percent.

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But 33% is an acceptable
approximation.

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Or we could take the
fractional form one-third

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and multiply that by 100.

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So 100 over three.

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Once again, we get
approximately 33.

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So 33%, and it doesn't
matter which way you do it.

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Change 0.7% into a
decimal and a fraction.

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So this is a very small
percent, less than one percent.

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We're going to change
it first to a decimal.

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So to change it to a decimal,
we need to divide it by 100.

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So we're going to take
the decimal point,

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which is right here,
and we're going

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to move it left two places.

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And we're going to
drop the symbol.

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So 0.7% is the same thing as
0.007, or what place is that?

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The thousandths place,
seven-thousandths.

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Now let's change
it to a fraction.

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Divide 0.7 by 100.

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Oh, now we've got a
decimal inside a fraction.

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Gross. So we need to
clear that decimal place.

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So we're going to multiply
it by the number one,

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which looks like 10 over 10,
because 10 times 0.7 is seven.

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There we go.

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So we cleared the decimal.

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What we do to the top we
have to do to the bottom,

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so now we multiply the bottom
by 10, and we get 1000.

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Seven-thousandths.

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But you already knew
that answer, didn't you?

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Because if you look
at the decimal answer

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and you say it correctly,

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seven-thousandths,
you're already there.

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Pause the video and
try these problems.

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Objective three.

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Percent equation.

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50 is 50% of 100.

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Let's translate this
into an equation.

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Is is a verb, so that's
where the equals goes.

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Of in mathematics
means multiply.

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So we have 50 is, which
is equals, 50% of,

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which is multiply, 100.

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50 equals 50% times 100.

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And recall that 50% is the
same thing as 50 over 100.

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And 50 over 100 reduces
to one-half.

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So another way to think of
this is 50 is one-half of 100.

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So to take 50% of something,

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that's the same thing
as taking half of it.

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What is 25% of 400?

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So let's translate
this into an equation.

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What, well, we'll call that
X. Is, well, that's equals.

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25% of, that's multiply, 400.

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So we have X equals
25% times 400.

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We could change 25%
into a decimal

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and multiply 0.25 times 400,
and if we had a calculator out,

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that's probably what I would do.

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But isn't there an easier way
if we're doing it by hand?

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Well, 25% of something is the
same as, well, as a fraction,

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25% is 25 over 100, which
reduces to one-fourth.

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So 25% of something
is the same thing

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as one-fourth of that thing.

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Think of money.

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A quarter, 25 cents.

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25 cents is a quarter
of a dollar, isn't it?

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So we could just take
one-quarter of that thing,

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in other words, multiply
it by one-fourth.

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In general, use the form of
the number, either fraction

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or decimal, that's easiest.

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So X equals one-fourth
times 400.

00:14:19.786 --> 00:14:20.436 A:middle
Let's do that.

00:14:20.906 --> 00:14:23.186 A:middle
We can cancel the four.

00:14:23.186 --> 00:14:24.626 A:middle
Four goes into four once.

00:14:24.676 --> 00:14:27.356 A:middle
Four goes into 400 100 times.

00:14:27.926 --> 00:14:29.586 A:middle
So X equals 100.

00:14:30.266 --> 00:14:34.496 A:middle
100 is 25% of 400.

00:14:38.376 --> 00:14:40.756 A:middle
Here are some common percentages

00:14:41.046 --> 00:14:42.956 A:middle
that would be good
to know as fractions.

00:14:43.556 --> 00:14:54.056 A:middle
10% is one-tenth, 20% is
one-fifth, 25% is one-fourth,

00:14:54.936 --> 00:14:59.416 A:middle
33 and a third percent, or
commonly rounded off to 33%,

00:14:59.636 --> 00:15:06.286 A:middle
is one-third, 50% is a
half, 66 and two-thirds,

00:15:06.386 --> 00:15:10.976 A:middle
or commonly rounded off
to just 67% is two-thirds,

00:15:12.216 --> 00:15:18.406 A:middle
75% is three-quarters,
and 100% is one.

00:15:19.136 --> 00:15:21.326 A:middle
When working with
these percentages,

00:15:21.496 --> 00:15:24.196 A:middle
it probably would be easier to
work with the fractional form

00:15:24.196 --> 00:15:26.456 A:middle
of a number instead
of the decimal form.

00:15:30.436 --> 00:15:34.266 A:middle
Example. What's 33% of $6000?

00:15:35.476 --> 00:15:41.626 A:middle
Well, what, we'll call that
X, is, that's equals, 33%,

00:15:42.366 --> 00:15:44.776 A:middle
of is times, and then 6000.

00:15:45.196 --> 00:15:49.946 A:middle
So X equals 33% times 6000.

00:15:50.556 --> 00:15:52.686 A:middle
What form of the
number is easier here?

00:15:53.026 --> 00:15:55.176 A:middle
One-third or 0.33?

00:15:56.026 --> 00:15:57.086 A:middle
Probably one-third.

00:15:57.446 --> 00:16:00.656 A:middle
So X equals one-third
times 6000.

00:16:01.576 --> 00:16:05.716 A:middle
Three goes into three once,
three goes into 6000 2000 times.

00:16:06.466 --> 00:16:11.956 A:middle
So 33% of $6000 is $2000.

00:16:16.096 --> 00:16:18.136 A:middle
What's 21% of 400?

00:16:18.706 --> 00:16:20.786 A:middle
Let's translate this
into an equation.

00:16:21.646 --> 00:16:28.536 A:middle
What, that's X, is,
equals, 21%, of, times, 400.

00:16:28.906 --> 00:16:31.976 A:middle
X equals 21% times 400.

00:16:32.586 --> 00:16:36.346 A:middle
For this problem, the decimal
form, which is 21 hundredths,

00:16:36.346 --> 00:16:38.966 A:middle
or 0.21, is the easiest to use.

00:16:39.496 --> 00:16:48.896 A:middle
So we're going to multiply
400 times 0.21 and we get 84.

00:16:49.626 --> 00:16:52.976 A:middle
So 21% of 400 is 84.

00:16:57.116 --> 00:17:01.596 A:middle
Example. What is 75% of $400?

00:17:02.136 --> 00:17:09.526 A:middle
What, that's X, is,
equals, 75%, of, times, 400.

00:17:10.136 --> 00:17:13.666 A:middle
So X equals 75% times 400.

00:17:14.526 --> 00:17:17.526 A:middle
Well, 75% of something
is the same thing

00:17:17.526 --> 00:17:19.006 A:middle
as three-quarters of that thing.

00:17:19.006 --> 00:17:23.836 A:middle
So I think the fractional form
would be easier to use here.

00:17:23.986 --> 00:17:27.276 A:middle
X equals three-quarters
times 400.

00:17:28.146 --> 00:17:31.306 A:middle
We cancel the four out of the
numerator and the denominator,

00:17:32.426 --> 00:17:37.776 A:middle
so four goes into four once,
four goes into 400 100 times.

00:17:38.216 --> 00:17:42.076 A:middle
So now we have three
times 100, which is 300.

00:17:43.186 --> 00:17:48.576 A:middle
75% of $400 is $300.

00:17:53.706 --> 00:17:57.686 A:middle
Example. What is 142% of 5000?

00:17:58.726 --> 00:18:04.726 A:middle
So we have X equals
142% times 5000.

00:18:05.816 --> 00:18:09.546 A:middle
For this problem, the
decimal form, which is 1.42,

00:18:09.546 --> 00:18:10.886 A:middle
is the easiest to use.

00:18:11.586 --> 00:18:14.506 A:middle
Recall that you divide by
100, which moves the decimal

00:18:14.506 --> 00:18:15.876 A:middle
to the left two places.

00:18:16.236 --> 00:18:17.916 A:middle
That's how I got 1.42.

00:18:18.426 --> 00:18:22.526 A:middle
So we take 5000 times 1.42.

00:18:23.116 --> 00:18:26.106 A:middle
That gives us $7100.

00:18:26.306 --> 00:18:31.346 A:middle
So 142% of 5000 is 7100.

00:18:31.816 --> 00:18:34.296 A:middle
Does that make sense?

00:18:35.096 --> 00:18:37.396 A:middle
It's always a good idea
to check to make sure

00:18:37.396 --> 00:18:38.816 A:middle
that your answer is reasonable.

00:18:39.386 --> 00:18:46.256 A:middle
142%. Well, that's 100%
plus 42%, isn't it?

00:18:46.626 --> 00:18:50.626 A:middle
Well 100% of 5000
is, well, 5000.

00:18:50.876 --> 00:18:53.166 A:middle
100% of anything is
that same number.

00:18:53.876 --> 00:18:57.386 A:middle
42% of it, well, that's
almost half of it.

00:18:57.386 --> 00:18:59.076 A:middle
Yeah, that's almost 50% of it.

00:18:59.206 --> 00:19:00.356 A:middle
And what's half of it?

00:19:00.636 --> 00:19:03.386 A:middle
Half of 5000 is 2500.

00:19:03.486 --> 00:19:11.726 A:middle
So 142% of 5000 should be a
little under 5000 plus 2500.

00:19:12.726 --> 00:19:14.456 A:middle
Well, that's 7500.

00:19:15.006 --> 00:19:20.196 A:middle
Our answer is 7100, a little
under 7500, so it makes sense.

00:19:20.496 --> 00:19:20.976 A:middle
It's reasonable.

00:19:25.556 --> 00:19:27.496 A:middle
Pause the video and
try these problems.

00:19:38.076 --> 00:19:40.536 A:middle
Objective for estimating
percentages.

00:19:41.046 --> 00:19:43.886 A:middle
It's often helpful to be
able to estimate percentages.

00:19:44.226 --> 00:19:45.946 A:middle
This is common when
you're trying to figure

00:19:45.946 --> 00:19:47.106 A:middle
out a tip or gratuity.

00:19:47.886 --> 00:19:53.566 A:middle
Example. Estimate a 15%
gratuity for a bill of $31.70.

00:19:54.216 --> 00:19:57.796 A:middle
Well, first of all, it's a good
idea to just round off your bill

00:19:57.796 --> 00:19:58.976 A:middle
to make it easier to work with.

00:19:59.426 --> 00:20:02.496 A:middle
Let's round $31.70 off to $32.

00:20:03.276 --> 00:20:08.216 A:middle
15%, well, that's 10% plus 5%,
so let's break it up that way.

00:20:08.806 --> 00:20:10.956 A:middle
What's 10% of $32?

00:20:11.356 --> 00:20:16.426 A:middle
Well, 10%, that's one-tenth,
so we're dividing $32 by 10.

00:20:17.046 --> 00:20:21.346 A:middle
That moves the decimal one place
to the left, so we get 3.2.

00:20:21.866 --> 00:20:26.876 A:middle
So 10% of 32 is 3.2.

00:20:27.396 --> 00:20:30.946 A:middle
5% of 32, well, that's
half of 10%, right?

00:20:30.996 --> 00:20:32.796 A:middle
5% is half of 10%?

00:20:33.546 --> 00:20:35.196 A:middle
So what's half of 3.2?

00:20:36.516 --> 00:20:37.826 A:middle
That's 1.6.

00:20:38.976 --> 00:20:45.006 A:middle
So 15% would be 10% plus 5%,
so we need to take the 3.2,

00:20:45.566 --> 00:20:50.216 A:middle
which was 10% of it, plus
the 1.6, which is 5% of it.

00:20:50.436 --> 00:20:53.346 A:middle
3.2 plus 1.6, that's 4.8.

00:20:54.056 --> 00:20:57.006 A:middle
I left off the extra zero just
to make it easier to work with.

00:20:57.826 --> 00:21:01.296 A:middle
So the tip should
be around $4.80.

00:21:05.666 --> 00:21:10.946 A:middle
Example. Estimate a 20%
gratuity for a bill of $78.95.

00:21:11.056 --> 00:21:14.736 A:middle
Well, let's round
$78.95 off to $80.

00:21:14.906 --> 00:21:16.546 A:middle
That makes it easier
to work with.

00:21:16.836 --> 00:21:20.156 A:middle
20%. Well, that's
twice 10%, yes?

00:21:20.596 --> 00:21:24.846 A:middle
So let's find out what 10% of
it is, and then we'll double it.

00:21:25.256 --> 00:21:29.186 A:middle
10% of $80, well,
that's one-tenth of $80.

00:21:29.186 --> 00:21:32.016 A:middle
Divide 80 by 10 and we get $8.

00:21:32.506 --> 00:21:35.146 A:middle
So 10% of $80 is $8.

00:21:35.806 --> 00:21:37.776 A:middle
20%, then, would be twice that.

00:21:38.056 --> 00:21:39.366 A:middle
What's twice $8?

00:21:39.696 --> 00:21:42.976 A:middle
$16. So the tip should
be around $16.

00:21:48.046 --> 00:21:49.936 A:middle
Pause the video and
try these problems.

00:22:00.806 --> 00:22:02.766 A:middle
Objective five.

00:22:02.766 --> 00:22:03.846 A:middle
Calculating tax.

00:22:04.306 --> 00:22:07.286 A:middle
Find the sales tax
on an E6B computer

00:22:07.826 --> 00:22:11.896 A:middle
if the selling price is
$26 and the tax rate is 8%.

00:22:12.896 --> 00:22:15.046 A:middle
So translating that
into an equation,

00:22:15.256 --> 00:22:19.596 A:middle
we have tax is 8% of 26.

00:22:20.206 --> 00:22:23.596 A:middle
So tax equals 8% times 26.

00:22:24.026 --> 00:22:27.796 A:middle
Let's use the decimal
form of 8%, which is 0.08.

00:22:28.666 --> 00:22:32.686 A:middle
26 times 0.08 is 2.08.

00:22:33.736 --> 00:22:36.776 A:middle
So the tax is $2.08.

00:22:43.556 --> 00:22:47.286 A:middle
A ticket agent must
calculate a 10% airport tax

00:22:47.586 --> 00:22:49.776 A:middle
on a ticket of $250.

00:22:50.426 --> 00:22:52.666 A:middle
How much in tax will the
customer have to pay?

00:22:53.716 --> 00:22:58.006 A:middle
So tax is 10% of 250.

00:22:58.756 --> 00:23:01.986 A:middle
So tax equals 10% times 250.

00:23:01.986 --> 00:23:03.466 A:middle
When we change it
into an equation,

00:23:04.486 --> 00:23:08.416 A:middle
10% is 10 over 100,
which is one-tenth.

00:23:09.596 --> 00:23:10.606 A:middle
Let's use this form,

00:23:10.606 --> 00:23:12.866 A:middle
the fractional form,
for 10% this time.

00:23:13.886 --> 00:23:18.236 A:middle
Tax equals one-tenth times 250.

00:23:18.236 --> 00:23:20.046 A:middle
We change 10% into one-tenth.

00:23:21.306 --> 00:23:23.426 A:middle
Canceling, we get 25.

00:23:24.526 --> 00:23:26.976 A:middle
The airport tax would be $25.

00:23:32.146 --> 00:23:33.976 A:middle
Pause the video and
try these problems.

00:23:44.466 --> 00:23:45.386 A:middle
Objective six.

00:23:46.186 --> 00:23:47.716 A:middle
Percent applications.

00:23:48.366 --> 00:23:52.066 A:middle
All employees of Zezic
Airlines are being asked

00:23:52.066 --> 00:23:53.736 A:middle
to take a 5% pay cut.

00:23:54.866 --> 00:23:57.426 A:middle
Your salary is $25,000 per year.

00:23:58.196 --> 00:24:00.726 A:middle
How much of a pay
cut will you receive?

00:24:01.986 --> 00:24:07.146 A:middle
Translating that into an
equation, pay cut is 5%

00:24:07.366 --> 00:24:10.116 A:middle
of the total, $25,000.

00:24:10.686 --> 00:24:15.216 A:middle
So pay cut equals
5% times 25,000.

00:24:16.286 --> 00:24:22.496 A:middle
If you choose to use a fraction,
5 over 100 times 25,000.

00:24:23.456 --> 00:24:26.776 A:middle
Cancel by dividing
top and bottom by 100.

00:24:27.456 --> 00:24:33.756 A:middle
And we have 5 times 250,
which gives us 1,250.

00:24:34.946 --> 00:24:36.716 A:middle
If you choose to use a decimal,

00:24:37.396 --> 00:24:42.506 A:middle
5% is five-hundredths,
or 0.05 as a decimal.

00:24:43.086 --> 00:24:49.866 A:middle
Multiply 25,000 times
0.05 and you get 1,250.

00:24:50.786 --> 00:24:53.976 A:middle
Your pay cut will be $1,250.

00:24:59.486 --> 00:25:00.816 A:middle
What will your new salary be?

00:25:01.426 --> 00:25:03.526 A:middle
Well, we need to take
the original salary

00:25:03.526 --> 00:25:07.756 A:middle
and subtract the pay
cut, which was $1,250.

00:25:08.176 --> 00:25:10.746 A:middle
So 25,000, which was
the original salary,

00:25:11.166 --> 00:25:16.316 A:middle
minus 1,250 gives us 23,750.

00:25:16.956 --> 00:25:20.496 A:middle
Your new salary will be $23,750.

00:25:21.366 --> 00:25:24.206 A:middle
But there actually is a
more straight-forward way

00:25:24.206 --> 00:25:25.586 A:middle
to calculate your new salary.

00:25:26.796 --> 00:25:29.966 A:middle
Since you're getting a pay
cut of 5% of your salary,

00:25:30.686 --> 00:25:35.106 A:middle
your new salary will
be 100% minus 5%,

00:25:35.426 --> 00:25:38.456 A:middle
which is 95% of your old salary.

00:25:39.166 --> 00:25:44.256 A:middle
New salary equals
95% of old salary.

00:25:45.716 --> 00:25:49.866 A:middle
95% as a decimal is
95-hundredths, or 0.95.

00:25:50.166 --> 00:25:54.206 A:middle
And if we multiply
25,000 times 0.95,

00:25:54.616 --> 00:25:58.976 A:middle
we get the same answer, $23,750.

00:26:04.516 --> 00:26:06.746 A:middle
Example. All employees

00:26:06.746 --> 00:26:09.546 A:middle
at Fly High Airlines are
now getting a 2% raise.

00:26:10.276 --> 00:26:12.576 A:middle
Your salary is $25,000 per year.

00:26:13.096 --> 00:26:14.386 A:middle
How much of a raise
will you get?

00:26:15.356 --> 00:26:20.946 A:middle
So pay raise is 2% of 25,000.

00:26:21.846 --> 00:26:26.686 A:middle
So pay raise equals
2% times 25,000.

00:26:27.306 --> 00:26:32.576 A:middle
Let's change 2% into a
decimal, 0.02 or two-hundredths.

00:26:33.796 --> 00:26:40.586 A:middle
Now we multiply 25,000
times 0.02 and we get $500.

00:26:41.476 --> 00:26:42.936 A:middle
Your raise will be $500.

00:26:48.086 --> 00:26:50.556 A:middle
What will your new salary be?

00:26:50.756 --> 00:26:53.906 A:middle
We need to take your original
salary and add in the pay raise.

00:26:54.376 --> 00:26:58.276 A:middle
So we take the $25,000
and add in 500,

00:26:58.706 --> 00:27:02.166 A:middle
and your new salary
will be $25,500.

00:27:03.076 --> 00:27:05.266 A:middle
Once again, there is a
more straight-forward way

00:27:05.266 --> 00:27:06.326 A:middle
to find your new salary.

00:27:07.156 --> 00:27:10.186 A:middle
Since you are getting a
raise of 2% of your salary,

00:27:10.656 --> 00:27:15.286 A:middle
your new salary will
be 100% plus 2%,

00:27:15.386 --> 00:27:18.816 A:middle
which is 102% of
your old salary.

00:27:19.426 --> 00:27:25.206 A:middle
So your new salary will be
102% of your old salary.

00:27:25.636 --> 00:27:30.076 A:middle
Let's change 102%
into a decimal, 1.02.

00:27:31.036 --> 00:27:37.186 A:middle
25,000 times 1.02 equals 25,500.

00:27:37.986 --> 00:27:41.586 A:middle
Once again, your new
salary will be $25,500.

00:27:46.746 --> 00:27:48.376 A:middle
Pause the video and
try these problems.