← Cubes and cube roots lesson New set →

Class 8 Maths Worksheet: Cubes and Cube Roots

Maths worksheets lesson 59: Cubes and cube roots · Set 632 · 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.What is ∛216? =
  2. 2.A big cube of edge 2 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  3. 3.A cube has a volume of 8 cubic cm. How long is each edge (in cm)?
  4. 4.What is the smallest whole number by which 392 must be multiplied to get a perfect cube?
  5. 5.A cube has a volume of 343 cubic cm. How long is each edge (in cm)?
  6. 6.A big cube of edge 18 cm is cut into small cubes of edge 3 cm. How many small cubes are there?
  7. 7.What is 20³? =
  8. 8.What is 19³? =
  9. 9.What is 14³? =
  10. 10.What is 11³? =
  11. 11.What is 4³? =
  12. 12.What is the smallest whole number by which 675 must be divided to get a perfect cube?
  13. 13.Which of these is a perfect cube? (a) 44 (b) 27 (c) 31
  14. 14.A big cube of edge 3 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  15. 15.A cube has a volume of 6859 cubic cm. How long is each edge (in cm)?
  16. 16.What is 3³? =
  17. 17.What is the smallest whole number by which 1600 must be multiplied to get a perfect cube?
  18. 18.What is ∛5832? =
  19. 19.Which of these is a perfect cube? (a) 194 (b) 158 (c) 125
  20. 20.What is 6³? =
  21. 21.A big cube of edge 12 cm is cut into small cubes of edge 3 cm. How many small cubes are there?
  22. 22.What is the smallest whole number by which 1080 must be multiplied to get a perfect cube?
  23. 23.What is the smallest whole number by which 243 must be multiplied to get a perfect cube?
  24. 24.Which of these is a perfect cube? (a) 1331 (b) 1643 (c) 1675
  25. 25.Which of these is a perfect cube? (a) 1061 (b) 1007 (c) 1000
  26. 26.What is ∛12167? =
  27. 27.Which of these is a perfect cube? (a) 512 (b) 540 (c) 520
  28. 28.A big cube of edge 4 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  29. 29.What is 12³? =
  30. 30.What is ∛1728? =
  31. 31.A cube has a volume of 5832 cubic cm. How long is each edge (in cm)?
  32. 32.Which of these is a perfect cube? (a) 317 (b) 216 (c) 221
  33. 33.Which of these is a perfect cube? (a) 907 (b) 943 (c) 729
  34. 34.A cube has a volume of 1728 cubic cm. How long is each edge (in cm)?
  35. 35.What is ∛13824? =
  36. 36.What is 13³? =
  37. 37.What is the smallest whole number by which 576 must be divided to get a perfect cube?
  38. 38.What is ∛2197? =
  39. 39.Which of these is a perfect cube? (a) 3669 (b) 3774 (c) 3375
  40. 40.A big cube of edge 8 cm is cut into small cubes of edge 4 cm. How many small cubes are there?

Answer key

  1. 6
  2. 8
  3. 2
  4. 7
  5. 7
  6. 216
  7. 8000
  8. 6859
  9. 2744
  10. 1331
  11. 64
  12. 25
  13. 27
  14. 27
  15. 19
  16. 27
  17. 5
  18. 18
  19. 125
  20. 216
  21. 64
  22. 25
  23. 3
  24. 1331
  25. 1000
  26. 23
  27. 512
  28. 8
  29. 1728
  30. 12
  31. 18
  32. 216
  33. 729
  34. 12
  35. 24
  36. 2197
  37. 9
  38. 13
  39. 3375
  40. 8

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