Year 8 Maths — Cubes and cube roots
Cube a number, recognise a perfect cube, and find a cube root by prime factorisation.
Name: ________________________
1.Put these in order by value, smallest first.
- The cube of 3
- The cube root of 64
- The cube root of 8000
- The cube of 2
- The cube root of 8
2.What happens when a negative number is cubed?
- a) It becomes zero
- b) It stays negative
- c) A negative number cannot be cubed
- d) It turns positive
3.What is the cube root of 1000?
4.Which of these is a perfect cube?
- a) 600
- b) 512
- c) 500
- d) 1200
5.What is the cube root of -125?
6.The prime factors of 5832 are 2 × 2 × 2 × 3 × 3 × 3 × 3 × 3 × 3. What is the cube root of 5832?
7.What is 7 cubed?
8.Match each number to its cube.
- 2
- 3
- 5
- 9
- 11
- 27
- 8
- 729
- 1331
- 125
Answer key — Year 8 Maths — Cubes and cube roots
- 1. 1. The cube root of 8 2. The cube root of 64 3. The cube of 2 4. The cube root of 8000 5. The cube of 3
- 2. b) It stays negative
- 3. 10
- 4. b) 512
- 5. -5
- 6. 18
- 7. 343
- 8. 2 → 8; 3 → 27; 5 → 125; 9 → 729; 11 → 1331