
Concept explainers
E. Calculator Problems
You probably own a calculator and, of course, you are eager to put it to work doing practical math calculations. In this text we include problem sets for calculator users. These problems are taken from real-life situations and, unlike most textbook problems, involve big numbers and lots of calculations. If you think that having an electronic brain-in-a-box means that you do not need to know basic arithmetic, you will be disappointed. The calculator helps you to work faster, but it will not tell you what to do or how to do it.
Detailed instructions on using a calculator with whole numbers appears on page 68.
Here are a few helpful hints for calculator users:
- 1. Always estimate your answer before doing a calculation.
- 2. Check your answer by comparing it with the estimate or by the other methods shown in this text. Be certain that your answer makes sense.
- 3. If you doubt the calculator (they do break down, you know), put a problem in it whose answer you know, preferably a problem like the one you are solving.
Trades Management Joe’s Air Conditioning Installation Co. has not been successful, and he is wondering if he should sell it and move to a better location. During the first three months of the year, his expenses were as follows:
His monthly income was:
January $1760
February $2650
March $3325
- (a) What was his total expense for the three-month period?
- (b) What was his total income for the three-month period?
- (c) Now turn your calculator around to learn what Joe should do about this unhappy situation.

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Chapter 1 Solutions
EBK MATHEMATICS FOR THE TRADES
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