The Algebra Teacher\'s Guide to Reteaching Essential Concepts and Skills

Teaching Notes 2.16: Expressing Percents as Fractions

Expressing percents as fractions is relatively easy for most students. A common problem involves

afractionsuchas

1

5

percent or a mixed number such as 33

1

3

percent.

1. Explain that ‘‘percent’’ means a rate per hundred. Thus, 3 percent means 3 out of 100 or

3

100

,

29 percent means 29 out of 100 or

29

100

, and 153 percent means 153 out of 100 or

153

100

or

1

53

100

.

2. Explain that all percents can be expressed as fractions, mixed numbers, or whole numbers.


3. Review the two methods on the worksheet for expressing percents as rational numbers and
   also review the examples.
   
   
   • Note that in method 1, students change the percent to a fraction and simplify. Point out
     that because percents are based on hundredths, the denominator of the fraction must be
     100. Students should always simplify, if possible.
   
   
   • Explain that method 2 is best used for percents that do not convert directly to fractions
     with a denominator of 100. Emphasize that this method works best with percents that are
     fractions or mixed numbers.
   
   
   
   

EXTRA HELP:

All percents greater than or equal to 100 percent will be expressed as whole numbers or mixed

numbers.

ANSWER KEY:

(1)

89

100

(2)

3

200

(3)

3

50

(4)

1

3

(5)

1

6

(6) 1

1

2

(7)

3

1000

(8)

5

9

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(Challenge)Yes. Answers may vary. Every increase of 11

1

9

percent results in an increase of

1

9

.66

2

3

percent is equivalent to 66

6

9

percent which equals

6

9

and satisfies the pattern.

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