5.3.3 Working with Negative Numbers by Hand

Activity symbol Activity: Multiplying and Dividing Negative Numbers

Work out the following calculations by hand in your math notebook.

After doing the work by hand, check your results on the calculator.

Calculator symbol The calculator can be accessed on the left-hand side bar under Toolkit.

(a) open three minus close multiplication five

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Discussion

Use the four rules for multiplying and dividing (Section 5.3.2) to determine the sign on your answer first, then carry out the operation without worrying about the signs.

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Answer

(a) equation left hand side open three minus close multiplication five equals right hand side one minus times five, since a negative number multiplied by a positive number gives a negative result.

(b) open three minus close multiplication open five minus close

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Answer

(b) open three minus close multiplication open five minus close equals 15, since a negative number multiplied by a negative number gives a positive result.

(c) open one minus times zero close division five

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Answer

(c) equation left hand side open one minus times zero close division five equals right hand side two minus since a negative number divided by a positive number gives a negative result.

(d) open one minus times zero close division open two minus close

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Answer

(d) open one minus times zero close division open two minus close equals five, since a negative number divided by a negative number gives a positive result.

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[ If you’d like some more explanation and extra practice with multiplication and negative numbers, visit this page. You can also create your own examples and check with the calculator. ]

You can also try using your multiplication skills with negative numbers in Grade or No Grade? to win the A+ from the “banker”.

5.3.2 Rules for Multiplication and Division of Signed Numbers

5.3.4 Negative Numbers Used in Golf