Basic Mathematics for College Students

Some percents occur so frequently that it is useful to memorize their fractional

and decimal equivalents.

508 Chapter 6 Percent

EXAMPLE 12

Write as a percent. Give the exact answer and an

approximation to the nearest tenth of one percent.

StrategyWe will write the fraction as a decimal. Then we will write that decimal

as a percent.

WHYA fraction-to-decimal-to-percent approach must be used to write a fraction

as a percent.

Solution

Step 1To write as a decimal, we divide the numerator, 5, by the denominator, 6.

The result is a repeating decimal.

Step 2To write the decimal as a percent, we proceed as follows.

Multiply 0.8333... by 100 by moving the decimal point

2 places to the right, and then insert a % symbol.

We must now decide whether we want an exact answer or an approximation. For an

exact answer, we can represent the repeating part of the decimal using an equivalent

fraction.For an approximation, we can round 83.333.. .% to a specific place value.

83.33.. .%

0.833.. .0 8 3.33.. .%

5

6

0.8333...

Write a decimal point and several zeros to the right of 5.

 The repeating pattern is now clear. We can stop the division.

0.8333

(^6)  5 .0000
4 8
20
 18
20
 18
20
 18
2
56
56

5

6

Self Check 12

Write as a percent. Give

the exact answer and an

approximation to the nearest

tenth of one percent.

Now TryProblem 91

23









Exact answer:

Use the fraction to

represent .3333....

Thus,

Approximation:

Round to the

nearest tenth.

Thus,

5

6

83.3%

 83.3%

5

6

83.33... %

5

6

 83

1

3

%

1

 83 1 3

3

%

5

6

 83 .3333... %

Percent Decimal Fraction

1% 0.01

10% 0.1

0.1666...

20% 0.2

25% 0.25

1

4

1

5

1

6

16 23 %

1

10

1

100

Percent Decimal Fraction

0.3333...

50% 0.5

0.6666...

0.8333...

75% 0.75

3

4

5

6

83 13 %

2

3

66 23 %

1

2

1

3

33 13 %



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