Page 55 - Basic College Mathematics with Early Integers
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32 C HAPTE R 1 I THE WHOLE NUMBERS
PRACTICE 6 Example 6 Calculating Miles per Gallon
During a sale, the price of a
A subcompact car gets 42 miles per gallon of gas. A full-size car gets 17 miles per
new suit is decreased by $47. If
gallon of gas. Find the difference between the subcompact car miles per gallon and
the original price was $92, find
the full-size car miles per gallon.
the sale price of the suit.
Solution: In Words Translate to Numbers
3 12
subcompact miles per gallon ¡ 4 2
- full-size miles per gallon ¡ - 1 7
difference in miles per gallon 2 5
The difference in the subcompact car miles per gallon and the full-size car miles
per gallon is 25 miles per gallon.
Work Practice 6
Once again, because subtraction and addition are reverse operations, don’t for-
get that a subtraction problem can be checked by adding.
Calculator Explorations Subtracting Numbers
To subtract numbers on a calculator, find the keys marked Use a calculator to subtract.
- and = or ENTER .
1. 865 - 95 2. 76 - 27
For example, to find 83 - 49 on a calculator, press the 3. 147 - 38 4. 366 - 87
keys 83 - 49 = or ENTER . 5. 9625 - 647 6. 10,711 - 8925
The display will read 34 .Thus, 83 - 49 = 34.
Copyright 2012 Pearson Education, Inc.
Answer
6. $45
