Chapter 6: Percents

42430_Cleaves_ch06 4/12/04 1:22 PM Page 175
Ti p
Multiplying by 1 in the Form of 100%
To write a number as its percent equivalent, identify the number as a fraction, whole number,
100%
or decimal. If the number is a fraction, multiply it by 1 in the form of 1
. If the number is
a whole number or decimal, multiply by 100% by using the shortcut rule for multiplying by
100. In each case, the percent equivalent will be expressed with a percent symbol.
EXAMPLE Write the decimal or whole number as a percent.
(a) 0.27 (b) 0.875 (c) 1.73 (d) 0.004 (e) 2
(a) 0.27 0.27 100% 027.% 27%
0.27 as a percent is 27%.
(b) 0.875 0.875 100% 087.5% 87.5%
0.875 as a percent is 87.5%.
(c) 1.73 1.73 100% 173.% 173%
1.73 as a percent is 173%.
(d) 0.004 0.004 100% 000.4% 0.4%
0.004 as a percent is 0.4%
(e) 2 2 100% 200.% 200%
2 as a percent is 200%.
Multiply 0.27 by 100% (move the
decimal point two places to the right).
Multiply 0.875 by 100% (move the
decimal point two places to the right).
Multiply 1.73 by 100% (move the
decimal point two places to the right).
Multiply 0.004 by 100% (move the
decimal point two places to the right).
Multiply 2 by 100% (move the
decimal point two places to the right).
As you can see, the procedure is the same regardless of the number of decimal places in the
number and regardless of whether the number is greater than, equal to, or less than 1.
EXAMPLE Write the fraction as a percent.
67 1
7 2
(a) (b) (c) 3 1 (d) (e)
100 4 2 4 3
1
67 67 100%
(a) = × = 67% Reduce and multiply.
100 100 1
(b)
(c) 3 1 2
(d)
(e)
1
4
7
4
2
3
25
1 100%
= × = 25 %
4 1
1
3 1 100%
7 100%
= × = × = 350%
2 1 2 1
7 100%
= × = 175%
4 1
1
1
25
2 100% 200% 2
= × = = 66
3 1 3 3 %
1
50
Reduce and multiply.
Change to an improper fraction, reduce,
and multiply.
Reduce and multiply.
Multiply.
STOP and Check
Write the decimal or whole number as a percent.
1. 0.82
2. 3.45
82%
345%
Write the fraction as a percent.
43
3
5.
6.
100
10
43%
30%
3. 0.0007
0.07%
7.
8 1 4
825%
4. 5
500%
8.
1
6
16 2 3 %
Percents 175