Math 8 · Unit 1: Integers · Cambridge Lower Secondary Maths Stage 8

Questions

1. 1. Here is a sequence of multiplications. Which three multiplications continue it?

   • −2 × −4 = 8; −4 × −4 = 16; −6 × −4 = 24
   • −1 × −4 = −4; −3 × −4 = −12; −5 × −4 = −20
   • −1 × −4 = 4; −3 × −4 = 8; −5 × −4 = 12
   • −1 × −4 = 4; −3 × −4 = 12; −5 × −4 = 20
   Check

2. 2. Work out −5 × 8

   • 40
   • −40
   • 3
   • −13
   Check

3. 3. Work out −5 × −8

   • −13
   • 13
   • 40
   • −40
   Check

4. 4. Work out −9 × −11

   • 20
   • −99
   • 99
   • −20
   Check

5. 5. Work out −20 × −6

   • 26
   • 120
   • −120
   • −26
   Check

6. 6. Put these multiplications into two groups: positive and negative answers. Match each multiplication to its group.

   • −12 × −3
   • −4 × 9
   • 18 × 2
   • 9 × −4

   • Positive
   • Positive
   • Negative
   • Negative
   Check

7. 7. Copy and complete this multiplication table.

   Fill the blanks with these.

   • 2
   • 54
   • 32
   • 72
   • −20
   • −12
   • 24
   • −24
   • 10
   Check

8. 8. Work out (3 + 4) × 5

   • 23
   • −35
   • 35
   • 17
   Check

9. 9. Work out (3 + −4) × 5

   • 5
   • −15
   • −35
   • −5
   Check

10. 10. Work out (−3 + −4) × −5

    • 13
    • 35
    • −12
    • −35
    Check

11. 11. Work out (3 + −4) × −5

    • 5
    • −5
    • −35
    • 35
    Check

12. 12. Estimate the answers by rounding numbers to the nearest integer. −2.9 × −8.15

    • 16
    • 11
    • −24
    • 24
    Check

13. 13. Estimate the answers by rounding numbers to the nearest integer. 10.8 × −6.1

    • −66
    • −60
    • −72
    • 66
    Check

14. 14. Estimate the answers by rounding numbers to the nearest integer. (−8.8)²

    • 64
    • 72
    • −81
    • 81
    Check

15. 15. Estimate the answers by rounding numbers to the nearest integer. (−4.09)²

    • 16
    • 20
    • 8
    • −16
    Check

16. 16. Work out (−6)² + (−8)² − (−10)²

    • 200
    • 100
    • −200
    • 0
    Check

17. 17. This is a multiplication pyramid. Each number is the product of the two numbers below. For example, 3 × −2 = −6. Copy and complete the pyramid.

    Fill the blanks with these.

    • −96
    • −4
    • 12
    • 2
    • 96
    • −12
    • −8
    Check

18. 18. This is a multiplication pyramid. Each number is the product of the two numbers below. Which order of the numbers −2, −1, 3 and 4 on the bottom row makes the top number 3456?

    • 4, −2, 3, −1
    • 3, 4, −1, −2
    • −2, 3, 4, −1
    • 3, −2, −1, 4
    Check

19. 19. The product of two integers is −6. Which pair of integers could they be?

    • 2 and −3
    • 2 and 3
    • −2 and −3
    • 1 and 6
    Check

20. 20. The product of two integers is 6. Which pair of integers could they be?

    • 2 and −3
    • −2 and −3
    • 1 and −6
    • −2 and 3
    Check