Math 9 · Unit 3: Decimals, percentages and rounding · Cambridge Lower Secondary Maths Stage 9

Questions

1. 1. Match each power of 10 with the multiplication that gives the same answer. The first one has been done for you: × 10⁰ and × 1.

   • × 10¹
   • × 10²
   • × 10³
   • × 10⁴
   • × 10⁵

   • × 1000
   • × 10
   • × 100 000
   • × 100
   • × 10 000
   Check

2. 2. Complete the workings for this multiplication. Move the decimal point to the right: 5.8 × 10² = 5.8 × 100 = 580.

   Fill the blanks with these.

   • 10
   • 3.4
   • 34
   • 100
   • 340
   Check

3. 3. Complete the workings for this multiplication. Move the decimal point to the right: 5.8 × 10² = 5.8 × 100 = 580.

   Fill the blanks with these.

   • 100
   • 48 000
   • 480
   • 1000
   • 4800
   Check

4. 4. Complete the workings for this multiplication. Move the decimal point to the right: 5.8 × 10² = 5.8 × 100 = 580.

   Fill the blanks with these.

   • 1250
   • 125
   • 12.5
   • 10
   • 100
   Check

5. 5. Complete the workings for this multiplication. Move the decimal point to the right: 5.8 × 10² = 5.8 × 100 = 580.

   Fill the blanks with these.

   • 100 000
   • 10 000
   • 50 000
   • 5 000 000
   • 500 000
   Check

6. 6. Complete the workings for this multiplication. Move the decimal point to the right: 5.8 × 10² = 5.8 × 100 = 580.

   Fill the blanks with these.

   • 140 000
   • 14 000
   • 100
   • 1000
   • 1400
   Check

7. 7. Match each multiplication by a negative power of 10 with the same division. The first one has been done for you: × 10⁻¹ and ÷ 10.

   • × 10⁻¹
   • × 10⁻²
   • × 10⁻³
   • × 10⁻⁴
   • × 10⁻⁵

   • ÷ 1000
   • ÷ 100 000
   • ÷ 10
   • ÷ 100
   • ÷ 10 000
   Check

8. 8. Complete the workings for this division. Move the decimal point to the left: 5.8 × 10⁻² = 5.8 ÷ 100 = 0.058.

   Fill the blanks with these.

   • 0.034
   • 0.0034
   • 10
   • 100
   • 0.34
   Check

9. 9. Complete the workings for this division. Move the decimal point to the left: 5.8 × 10⁻² = 5.8 ÷ 100 = 0.058.

   Fill the blanks with these.

   • 1000
   • 100
   • 0.008
   • 0.0008
   • 0.08
   Check

10. 10. Complete the workings for this division. Move the decimal point to the left: 5.8 × 10⁻² = 5.8 ÷ 100 = 0.058.

    Fill the blanks with these.

    • 0.00015
    • 10 000
    • 1000
    • 0.0015
    • 0.015
    Check

11. 11. Complete the workings for this division. Move the decimal point to the left: 5.8 × 10⁻² = 5.8 ÷ 100 = 0.058.

    Fill the blanks with these.

    • 100
    • 0.12
    • 1.2
    • 120
    • 10
    Check

12. 12. Work out 28 × 10².

    • 280
    • 2800
    • 28 000
    • 0.28
    Check

13. 13. Work out 2.8 × 10⁴.

    • 28 000
    • 2800
    • 0.000 28
    • 280 000
    Check

14. 14. Work out 28 × 10.

    • 28
    • 280
    • 2.8
    • 2800
    Check

15. 15. Work out 2.88 × 10³.

    • 2880
    • 28 800
    • 0.002 88
    • 288
    Check

16. 16. Work out 2.8 × 10⁵.

    • 280 000
    • 2 800 000
    • 0.000 028
    • 28 000
    Check

17. 17. Work out 0.02 × 10¹.

    • 0.002
    • 2
    • 0.021
    • 0.2
    Check

18. 18. Work out 28 × 10⁰.

    • 0
    • 2.8
    • 28
    • 280
    Check

19. 19. Work out 2 × 10⁻¹.

    • −20
    • 20
    • 0.2
    • 0.02
    Check

20. 20. Work out 2.8 × 10⁻².

    • 280
    • 0.28
    • 0.0028
    • 0.028
    Check