Page 7 - 新思维数学活动用书7 样章

1 Integers

5 Work out:
a 20 − −5 b −10 − −15 c −2 − −13 d −3 − 20

Practice
6 Fill in the missing numbers.

a 8 + = 1 b −3 + = 3
c −10 + = −6 d 5 + = −5
7 Fill in the missing numbers.
a − 3 = 6 b − 3 = 2

c − 3 = −1 d − 3 = −6
8 Estimate the answers to these questions by rounding the numbers to the nearest integer.
a −6.15 + 9.93 b 7.88 − −9.13
c −11.3 + −8.81 d 12.19 − 5.62

9 Estimate the answers to these questions by rounding the numbers.
a −28 − 53 b 514 + −321
c −888 − −111 d −61.1 + −29.3

10 Two integers add up to 2. One of the integers is 8. What is the other integer?
11 When you subtract one integer from another integer, the answer is 3.
One integer is 1. Find the other integer.
12 Here are six integers: −5, −3, −2, 3, 4, 5.
Use each integer once to complete these additions.
a + = 1 b + = −2 c + = 3

Challenge

13 Copy and complete this addition table.
+ 3

5 −2

1 −6

14 This subtraction table shows that 3 − 6 = −3. Copy and complete the table.

− −4 6
3 −3 1

−3

6