Page 10 - Cambridge+Checkpoint+Mathematics+Coursebook+9

1.1 Directed numbers

3 Work these out.
a 7 − −4 b −7 − 0.4 c −0.4 − −7 d −0.4 − 0.7 e −4 − −0.7
4 Work these out.
a 2.8 − −1.3 b 0.6 − −4.1 c −5.8 − 0.3 d −0.7 − 6.2 e −2.25 − −0.12
5 The midday temperature, in Celsius degrees (°C), on four successive
days is 1.5, −2.6, −3.4 and 0.5. Calculate the mean temperature.

6 Find the missing numbers.
a + 4 = 1.5 b + −6.3 = −5.9 c 4.3 + = −2.1 d 12.5 + = 3.5
7 Find the missing numbers.
a − 3.5 = −11.6 b − −2.1 = 4.1 c − 8.2 = 7.2 d − −8.2 = 7.2

8 Copy and complete this addition table.
+ −3.4 −1.2
5.1
−4.7

9 Use the information in the box to work these out. 2.3 × 9.6 = 22.08
a −2.3 × −9.6 b −22.08 ÷ 2.3 c 22.08 ÷ −9.6
d −4.6 × −9.6 e −11.04 ÷ −2.3

10 Work these out.
a 2.7 × −3 b 2.7 ÷ −3 c −1.2 × −1.2 d −3.25 × −4 e 17.5 ÷ −2.5

11 Copy and complete this multiplication table.
× 3.2 −0.6
−1.5
1.5

12 Complete these calculations.
a −2 × −3 b (−2 × −3) × −4 c (−3 × 4) ÷ −8
13 Use the values given in the box to work out the value of each expression.
a p − q b (p + q) × r
c (q + r) × p d (r − q) ÷ (q − p) p = −4.5 q = 5.5 r = −7.5

14 Here is a multiplication table. × 2.4 3.5 4.6
Use the table to calculate these.
a (−2.4) b 13.44 ÷ −4.6 2.4 5.76 8.4 13.44
2
c −16.1 ÷ −3.5 d −84 ÷ 2.4 3.5 8.4 12.25 16.1
4.6 13.44 16.1 21.16

15 p and q are numbers, p + q = 1 and pq = –20. What are the values of p and q?

1 Integers, powers and roots 9