Percent is a ratio that compares a number to 100 The symbol for percent is % Percent means “per...

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Transcript of Percent is a ratio that compares a number to 100 The symbol for percent is % Percent means “per...

Percent is a ratio that compares a number to 100

The symbol for percent is %

Percent means “per hundred”

So, is 17% 17100

40 % Means40 parts out of 100or40hundredths

Percents Have Equivalents in Decimals and Fractions

20% .20 20 100

15

== =

PercentDecimalFractionSimplifiedFraction

Find the percent of a Whole Number?

Remember“of” means multiply

of x=

Step1

When you see a percent problem, you know when you read “of” in the problem you multiply.

15% 100ofx

Step2Change your percent to a decimaland then move the decimal point

two places to the left.

15%x 100. .

Step3Multiply just like a regular decimal

multiplication problem

100x.150005

001+0051

Step 4

100x.150005

001+0051 ..

Place the decimal point 2 places to the left in your answer.

15Answer:

Practice

25% of 300x..300x.25

00510006+

0057

Move the decimal point 2 places to the left in your answer.

300x.25

00510006+

0057 .. Answer:75

You can also find the percent of a number by writing the percent as

a fraction and multiplying

25%of 401.Change the percent to a fraction

25100

=÷÷

2525

14

x 40

x 40 11

10

1 x 101 x 1

= 10 1

14

14

10

Practice

75%of 80

1.

75100

Simplify

÷÷

=2525

34

2. Multiply

34

x 80 11

20

3 x 201 x 1

==

601

= 60

Changing percents to fractionsTo express a percent as a fraction, write a fraction with a denominator of

100•Remember – a percent is a number “out of 100.”

65% = 65100

65100

÷÷

55

= 1320

Changing fractions to percentsTo express a fraction as

a percent, write a fraction with a

denominator of 100•Remember – a percent is a number “out of 100.”

14

= 14 x

x2525

=

25100

= 25%

25100