Page 16 - 新思维数学学生用书8 样章

1.2 Multiplying and dividing integers

Continued

c Here is the start of another sequence of multiplications.
−×54 =

−× =
53
−× =
52
Copy the sequence and write six more terms.
Describe any patterns in the sequence.

d In the sequences in a and c, you have some products of two negative
integers. What can you say about the product of two negative integers?
e Make up a sequence of your own like the ones in a and c.
f Share your answers to parts d and e with a partner. Are your partner’s

sequences correct?

2 Work out these multiplications.
a 5 ×− 2 b −×52 c −× − 2 d −× −5
5
2
3 Work out these multiplications.
a −× − 4 b −× − 7 c −10 × −6 d −8 × −11
7
6
4 Copy and complete this multiplication table.
× −5 3 −8

4
−3 −9
−6 30

5 Work out
a (3 + 5) × −4 b (−3 + −5) × −6 Tip
c −4 × (5 − 8) d −6 × (−2 − −7) Do the calculation

6 Round these numbers to the nearest whole number to estimate in brackets first.
the answer.
a 3.9 × −6.8 b −11.2 × 2.95

c (−6.1) 2 d (−4.88) 2
7 a Put these multiplications into groups based on the answers.
3 × −4 −6 × −2 12 × 1
−4 × −3 2 × −6 −12 × −1
b Find one more product to put in each group.

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