Name _____________________________________________________Date_________
Integer Addition (GPS M7N1)
Use the Excel Spreadsheet “Integer Sums” to answer the following questions:
1. Study the sums shown on the spreadsheet. Use this data to predict what the sum
of (-12) + 1 would be. ____________. Now drag the spreadsheet down 1 row to
test your answer. Were you correct? __________ Use the pattern to describe
how you could find the sum of any negative number and 1?
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2. Now go to top of the spreadsheet (cell B2) and change the second addend to a 2.
(Notice how the sums change). Predict what the sum of (-20) + 2 would be.
__________ Now drag the formulas down to check your answer. Were you
correct? _______ Study the patterns and describe how you could find the sum of
any negative number and 2.
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3. Go back to the top of the spreadsheet and change the second addend to a (-1).
Observe the changes in the sum. Record your prediction for the sum of (-50)+(-1)
________. Test your theory by dragging the formula in the spreadsheet.
Describe how you can find the sum of any negative number and (-1).
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4. Now change the second addend to a (-2). Observe the changes, test your
predictions and then describe below how you can find the sum of any negative
number and (-2).
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Try changing the addends several more times on your own and observe the changes.
Record the observations you make about adding two negative numbers together .
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Record the observations you make about adding a negative number with a positive
number.
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