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N4 Multiplying and dividing negative numbers

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Negative numbers in context

There are many real life situations which use negative numbers.

Temperature

Balance -$34.52

Bank balances

Games with negative scores.

Measurements taken below sea level

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–3 + –3 + –3 + –3 + –3 =

0–3–6–9–12

–3

–15

–15

5 × –3 = –15

A positive number × a negative number = a negative number

Multiplying and dividing integers

–3–3–3–3

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–4 × –6 =

0

– –6

6

– –6

12

– –6

18

– –6

24

24

A negative number × a negative number = a positive number

Multiplying and dividing negative numbers

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When multiplying negative numbers remember:

Rules for multiplying and dividing

Dividing is the inverse operation to multiplying.

When we are dividing negative numbers similar rules apply:

+ × + = +

–+ × = –

–+× =–

– +× =–

+ ÷ + = +

–+ ÷ = –

–+÷ =–

– +÷ =–

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3 × –8 ÷ = 1.5–16

–4 × –5 × –8 = –160

–7 × = 175–25

÷ –90 = –6540

–36 ÷ = –4

47 × = 141

42 ÷ = –6

–3 × 8 = –24

Multiplying and dividing integers

Complete the following:

–7

× –8 = 96–12

3

–72 ÷ –6 = 12

9

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Mixed division square

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Number spiral

3

–7–4

×2–8

–2 –10 ÷ –5

2

× –1

–2

+ 86÷ –2–3

× 5

–15

+ 4 –11– 5

–16+ 16

0

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