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Convert the following fractions, first to decimals, then to percents. Round percents to the nearest tenth
of a percent.

18. 1
8
19. 1
6
20. 2 5
21. 3
8
22. 3
4
1
23. 13
24. 1
12
25. 5
12

4.12 Fractional parts of numbers

We now have several ways of indicating a fractional part of a number. For example, the phrases

1
of 90
4
0.25 of 90

25% of 90

are all different ways of describing the number 1 4 × 90 = 22.5. The word “of” indicates multiplication.
In the case of percent, the multiplication is done after first converting the percent to a fraction or a
decimal.
The fractional part taken need not be a proper fractional part. That is, we could end up with more
than we started with.
Example 179. Find 125% of 500.

Solution. Converting the percent to the decimal 1.25, and then multiplying by 500, we get

1.25 × 500 = 625.

1
Example 180. Sales tax in New York State is 8 %. What is the sales tax on a shirt priced at $25?
4
1
Solution. 8 =8.25, and 8.25%, as a decimal, is .0825. So the sales tax on a $25 shirt is
4
.0825 × 25 = 2.0625 ≈ $2.06.

Note that we rounded off to the nearest cent.

Example 181. Josh spends 2 of his income on rent. If he earns $1250 per month, how much does he
5
have left over, after paying his rent?

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