← Cubes and cube roots lesson New set →

Class 8 Maths Worksheet: Cubes and Cube Roots

Maths worksheets lesson 59: Cubes and cube roots · Set 343 · 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) 51 (b) 36 (c) 27
  2. 2.Which of these is a perfect cube? (a) 75 (b) 64 (c) 73
  3. 3.Which of these is a perfect cube? (a) 4000 (b) 3641 (c) 3375
  4. 4.A big cube of edge 6 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  5. 5.A cube has a volume of 64 cubic cm. How long is each edge (in cm)?
  6. 6.What is 20³? =
  7. 7.What is ∛2744? =
  8. 8.What is 14³? =
  9. 9.What is the smallest whole number by which 81 must be divided to get a perfect cube?
  10. 10.A cube has a volume of 27 cubic cm. How long is each edge (in cm)?
  11. 11.What is ∛1728? =
  12. 12.A big cube of edge 9 cm is cut into small cubes of edge 3 cm. How many small cubes are there?
  13. 13.What is the smallest whole number by which 4 must be multiplied to get a perfect cube?
  14. 14.What is 8³? =
  15. 15.A big cube of edge 10 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  16. 16.What is ∛125? =
  17. 17.What is the smallest whole number by which 56 must be divided to get a perfect cube?
  18. 18.What is ∛8000? =
  19. 19.What is 7³? =
  20. 20.What is 15³? =
  21. 21.What is the smallest whole number by which 40 must be multiplied to get a perfect cube?
  22. 22.A big cube of edge 8 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  23. 23.What is the smallest whole number by which 576 must be divided to get a perfect cube?
  24. 24.What is ∛10648? =
  25. 25.What is 13³? =
  26. 26.What is 5³? =
  27. 27.What is 6³? =
  28. 28.What is ∛4913? =
  29. 29.What is ∛1000? =
  30. 30.What is 16³? =
  31. 31.A cube has a volume of 4096 cubic cm. How long is each edge (in cm)?
  32. 32.What is the smallest whole number by which 7 must be divided to get a perfect cube?
  33. 33.What is ∛27? =
  34. 34.A big cube of edge 20 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  35. 35.A big cube of edge 8 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  36. 36.A cube has a volume of 5832 cubic cm. How long is each edge (in cm)?
  37. 37.What is the smallest whole number by which 875 must be multiplied to get a perfect cube?
  38. 38.What is the smallest whole number by which 392 must be divided to get a perfect cube?
  39. 39.A big cube of edge 5 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  40. 40.A cube has a volume of 343 cubic cm. How long is each edge (in cm)?

Answer key

  1. 27
  2. 64
  3. 3375
  4. 27
  5. 4
  6. 8000
  7. 14
  8. 2744
  9. 3
  10. 3
  11. 12
  12. 27
  13. 2
  14. 512
  15. 125
  16. 5
  17. 7
  18. 20
  19. 343
  20. 3375
  21. 25
  22. 64
  23. 9
  24. 22
  25. 2197
  26. 125
  27. 216
  28. 17
  29. 10
  30. 4096
  31. 16
  32. 7
  33. 3
  34. 125
  35. 8
  36. 18
  37. 49
  38. 49
  39. 125
  40. 7

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