← Cubes and cube roots lesson New set →

Class 8 Maths Worksheet: Cubes and Cube Roots

Maths worksheets lesson 59: Cubes and cube roots · Set 824 · 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) 125 (b) 183 (c) 137
  2. 2.What is ∛6859? =
  3. 3.A cube has a volume of 3375 cubic cm. How long is each edge (in cm)?
  4. 4.A cube has a volume of 27 cubic cm. How long is each edge (in cm)?
  5. 5.A big cube of edge 5 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  6. 6.What is the smallest whole number by which 32 must be multiplied to get a perfect cube?
  7. 7.What is 4³? =
  8. 8.Which of these is a perfect cube? (a) 1663 (b) 1331 (c) 1372
  9. 9.A cube has a volume of 1728 cubic cm. How long is each edge (in cm)?
  10. 10.What is ∛10648? =
  11. 11.A cube has a volume of 512 cubic cm. How long is each edge (in cm)?
  12. 12.What is 16³? =
  13. 13.What is ∛3375? =
  14. 14.What is ∛8? =
  15. 15.A big cube of edge 6 cm is cut into small cubes of edge 3 cm. How many small cubes are there?
  16. 16.A cube has a volume of 216 cubic cm. How long is each edge (in cm)?
  17. 17.What is the smallest whole number by which 375 must be divided to get a perfect cube?
  18. 18.What is 8³? =
  19. 19.Which of these is a perfect cube? (a) 65 (b) 64 (c) 104
  20. 20.A cube has a volume of 5832 cubic cm. How long is each edge (in cm)?
  21. 21.What is the smallest whole number by which 675 must be divided to get a perfect cube?
  22. 22.What is ∛27? =
  23. 23.What is ∛4913? =
  24. 24.A cube has a volume of 729 cubic cm. How long is each edge (in cm)?
  25. 25.Which of these is a perfect cube? (a) 2975 (b) 2744 (c) 2950
  26. 26.What is the smallest whole number by which 432 must be multiplied to get a perfect cube?
  27. 27.A big cube of edge 10 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  28. 28.What is 14³? =
  29. 29.A big cube of edge 15 cm is cut into small cubes of edge 3 cm. How many small cubes are there?
  30. 30.What is the smallest whole number by which 7 must be divided to get a perfect cube?
  31. 31.What is the smallest whole number by which 7 must be multiplied to get a perfect cube?
  32. 32.A cube has a volume of 64 cubic cm. How long is each edge (in cm)?
  33. 33.A cube has a volume of 1000 cubic cm. How long is each edge (in cm)?
  34. 34.A cube has a volume of 4096 cubic cm. How long is each edge (in cm)?
  35. 35.What is the smallest whole number by which 432 must be divided to get a perfect cube?
  36. 36.What is the smallest whole number by which 864 must be divided to get a perfect cube?
  37. 37.What is the smallest whole number by which 3 must be multiplied to get a perfect cube?
  38. 38.What is ∛15625? =
  39. 39.A cube has a volume of 8 cubic cm. How long is each edge (in cm)?
  40. 40.What is 12³? =

Answer key

  1. 125
  2. 19
  3. 15
  4. 3
  5. 125
  6. 2
  7. 64
  8. 1331
  9. 12
  10. 22
  11. 8
  12. 4096
  13. 15
  14. 2
  15. 8
  16. 6
  17. 3
  18. 512
  19. 64
  20. 18
  21. 25
  22. 3
  23. 17
  24. 9
  25. 2744
  26. 4
  27. 125
  28. 2744
  29. 125
  30. 7
  31. 49
  32. 4
  33. 10
  34. 16
  35. 2
  36. 4
  37. 9
  38. 25
  39. 2
  40. 1728

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