← Cubes and cube roots lesson New set →

Class 8 Maths Worksheet: Cubes and Cube Roots

Maths worksheets lesson 59: Cubes and cube roots · Set 984 · 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) 1687 (b) 1494 (c) 1331
  2. 2.Which of these is a perfect cube? (a) 48 (b) 27 (c) 28
  3. 3.A big cube of edge 6 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  4. 4.Which of these is a perfect cube? (a) 1073 (b) 1000 (c) 1050
  5. 5.What is ∛9261? =
  6. 6.A big cube of edge 6 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  7. 7.What is the smallest whole number by which 500 must be multiplied to get a perfect cube?
  8. 8.What is ∛125? =
  9. 9.What is ∛4913? =
  10. 10.What is ∛64? =
  11. 11.What is the smallest whole number by which 108 must be divided to get a perfect cube?
  12. 12.What is the smallest whole number by which 54 must be divided to get a perfect cube?
  13. 13.What is 5³? =
  14. 14.What is the smallest whole number by which 1512 must be divided to get a perfect cube?
  15. 15.Which of these is a perfect cube? (a) 357 (b) 366 (c) 343
  16. 16.A cube has a volume of 64 cubic cm. How long is each edge (in cm)?
  17. 17.A cube has a volume of 5832 cubic cm. How long is each edge (in cm)?
  18. 18.What is 20³? =
  19. 19.A cube has a volume of 729 cubic cm. How long is each edge (in cm)?
  20. 20.A big cube of edge 16 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  21. 21.What is the smallest whole number by which 4 must be multiplied to get a perfect cube?
  22. 22.A big cube of edge 8 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  23. 23.What is the smallest whole number by which 72 must be multiplied to get a perfect cube?
  24. 24.A cube has a volume of 125 cubic cm. How long is each edge (in cm)?
  25. 25.A cube has a volume of 8 cubic cm. How long is each edge (in cm)?
  26. 26.What is the smallest whole number by which 32 must be divided to get a perfect cube?
  27. 27.What is 3³? =
  28. 28.What is ∛216? =
  29. 29.Which of these is a perfect cube? (a) 535 (b) 512 (c) 532
  30. 30.A cube has a volume of 3375 cubic cm. How long is each edge (in cm)?
  31. 31.What is ∛15625? =
  32. 32.What is 18³? =
  33. 33.What is ∛4096? =
  34. 34.What is ∛1331? =
  35. 35.Which of these is a perfect cube? (a) 3940 (b) 3527 (c) 3375
  36. 36.What is 15³? =
  37. 37.What is 8³? =
  38. 38.What is ∛12167? =
  39. 39.What is 2³? =
  40. 40.What is the smallest whole number by which 189 must be multiplied to get a perfect cube?

Answer key

  1. 1331
  2. 27
  3. 216
  4. 1000
  5. 21
  6. 27
  7. 2
  8. 5
  9. 17
  10. 4
  11. 4
  12. 2
  13. 125
  14. 7
  15. 343
  16. 4
  17. 18
  18. 8000
  19. 9
  20. 64
  21. 2
  22. 8
  23. 3
  24. 5
  25. 2
  26. 4
  27. 27
  28. 6
  29. 512
  30. 15
  31. 25
  32. 5832
  33. 16
  34. 11
  35. 3375
  36. 3375
  37. 512
  38. 23
  39. 8
  40. 49

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