← Cubes and cube roots lesson New set →

Class 8 Maths Worksheet: Cubes and Cube Roots

Maths worksheets lesson 59: Cubes and cube roots · Set 211 · 40 sums
TalentJR

The method (Threes make cubes): Cube: n × n × n. Cube root: the number that, used three times, gives the cube. Units digits: 1→1, 2→8, 3→7, 4→4, 5→5, 6→6, 7→3, 8→2, 9→9, 0→0 — use them to guess cube roots. Make a perfect cube: break into primes; multiply by what completes each group of three (or divide by what is left over). A big cube of edge a cut into small cubes of edge b gives (a ÷ b)³ small cubes.

NameDateTime takenScore ___ / 40
  1. 1.Which of these is a perfect cube? (a) 957 (b) 836 (c) 729
  2. 2.A big cube of edge 16 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  3. 3.Which of these is a perfect cube? (a) 3943 (b) 3709 (c) 3375
  4. 4.A big cube of edge 5 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  5. 5.A big cube of edge 4 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  6. 6.Which of these is a perfect cube? (a) 125 (b) 160 (c) 192
  7. 7.Which of these is a perfect cube? (a) 1436 (b) 1331 (c) 1530
  8. 8.What is 8³? =
  9. 9.What is 5³? =
  10. 10.A big cube of edge 12 cm is cut into small cubes of edge 3 cm. How many small cubes are there?
  11. 11.A big cube of edge 24 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  12. 12.A big cube of edge 8 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  13. 13.A big cube of edge 20 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  14. 14.What is the smallest whole number by which 648 must be multiplied to get a perfect cube?
  15. 15.What is ∛343? =
  16. 16.What is the smallest whole number by which 32 must be divided to get a perfect cube?
  17. 17.Which of these is a perfect cube? (a) 86 (b) 81 (c) 64
  18. 18.What is the smallest whole number by which 128 must be multiplied to get a perfect cube?
  19. 19.A big cube of edge 6 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  20. 20.A cube has a volume of 343 cubic cm. How long is each edge (in cm)?
  21. 21.What is ∛729? =
  22. 22.What is ∛12167? =
  23. 23.Which of these is a perfect cube? (a) 659 (b) 512 (c) 680
  24. 24.What is ∛6859? =
  25. 25.What is 6³? =
  26. 26.What is ∛10648? =
  27. 27.Which of these is a perfect cube? (a) 29 (b) 51 (c) 27
  28. 28.What is ∛27? =
  29. 29.What is ∛8000? =
  30. 30.What is ∛1728? =
  31. 31.Which of these is a perfect cube? (a) 1728 (b) 2001 (c) 1837
  32. 32.A cube has a volume of 3375 cubic cm. How long is each edge (in cm)?
  33. 33.A big cube of edge 10 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  34. 34.Which of these is a perfect cube? (a) 288 (b) 244 (c) 216
  35. 35.A cube has a volume of 6859 cubic cm. How long is each edge (in cm)?
  36. 36.What is 15³? =
  37. 37.What is ∛13824? =
  38. 38.What is ∛9261? =
  39. 39.What is ∛2197? =
  40. 40.What is the smallest whole number by which 72 must be multiplied to get a perfect cube?

Answer key

  1. 729
  2. 64
  3. 3375
  4. 125
  5. 8
  6. 125
  7. 1331
  8. 512
  9. 125
  10. 64
  11. 216
  12. 64
  13. 125
  14. 9
  15. 7
  16. 4
  17. 64
  18. 4
  19. 27
  20. 7
  21. 9
  22. 23
  23. 512
  24. 19
  25. 216
  26. 22
  27. 27
  28. 3
  29. 20
  30. 12
  31. 1728
  32. 15
  33. 125
  34. 216
  35. 19
  36. 3375
  37. 24
  38. 21
  39. 13
  40. 3

Free maths worksheets lessons, practice and worksheets at talentjr.in/maths-worksheets