Chapter Review
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Remember the definitions of integers and absolute value.
See solution.
Our goal is to describe how we use integers and absolute value in real-world situations. Let's start with integers.
Remember that integers are all positive and negative numbers that do not contain any decimal parts. Zero is also an integer.
... - 2, - 1, 0,1,2 ...
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The outside temperature in Toronto, Canada was 3 ^(∘)C. The temperature dropped 5 degrees. Find the current temperature in Toronto. |
Notice that all of the numbers used in the problem are integers. Now, to find the current temperature, we subtract 5 from 3. Let's do it! 3-5 = - 2 The temperature in Toronto is currently - 2 ^(∘)C. Notice that the result is also an integer.
Absolute value is the distance between a number and 0 on a number line.
Absolute value has many uses in the everyday world. For example, if we add the absolute values of our receipts in our wallet, we get our spending. Here is a sample list of our receipts. Coffee:& - $ 3 Bus Fare:& - $ 2 Lunch:& - $ 17 To find our spending, we first calculate the absolute value of each value. Remember that to calculate the absolute value of a negative number, we drop its sign. | - 3|&=3 | - 2|&=2 | - 17|&=17 Then to find the total money we spent, we add the absolute values. 3+2+17=22 We spent a total of 22 dollars today.
We use integers to express many values that surround is in our daily life. Absolute value helps us find the size of these values.