← Cubes and cube roots lesson New set →

Class 8 Maths Worksheet: Cubes and Cube Roots

Maths worksheets lesson 59: Cubes and cube roots · Set 382 · 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.A cube has a volume of 2744 cubic cm. How long is each edge (in cm)?
  2. 2.Which of these is a perfect cube? (a) 2008 (b) 1728 (c) 1835
  3. 3.A big cube of edge 6 cm is cut into small cubes of edge 3 cm. How many small cubes are there?
  4. 4.What is the smallest whole number by which 1512 must be multiplied to get a perfect cube?
  5. 5.What is ∛10648? =
  6. 6.A cube has a volume of 512 cubic cm. How long is each edge (in cm)?
  7. 7.What is ∛27? =
  8. 8.A big cube of edge 4 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  9. 9.What is ∛125? =
  10. 10.What is the smallest whole number by which 432 must be multiplied to get a perfect cube?
  11. 11.What is ∛6859? =
  12. 12.Which of these is a perfect cube? (a) 3375 (b) 3450 (c) 3515
  13. 13.A cube has a volume of 64 cubic cm. How long is each edge (in cm)?
  14. 14.What is the smallest whole number by which 448 must be multiplied to get a perfect cube?
  15. 15.A big cube of edge 18 cm is cut into small cubes of edge 3 cm. How many small cubes are there?
  16. 16.What is ∛12167? =
  17. 17.A big cube of edge 5 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  18. 18.Which of these is a perfect cube? (a) 1000 (b) 1141 (c) 1076
  19. 19.What is ∛15625? =
  20. 20.A big cube of edge 12 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  21. 21.What is 2³? =
  22. 22.A big cube of edge 6 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  23. 23.A cube has a volume of 729 cubic cm. How long is each edge (in cm)?
  24. 24.A big cube of edge 16 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  25. 25.What is 17³? =
  26. 26.What is 11³? =
  27. 27.What is 13³? =
  28. 28.What is 19³? =
  29. 29.What is 9³? =
  30. 30.What is ∛512? =
  31. 31.What is the smallest whole number by which 25 must be divided to get a perfect cube?
  32. 32.What is the smallest whole number by which 3 must be divided to get a perfect cube?
  33. 33.What is the smallest whole number by which 500 must be divided to get a perfect cube?
  34. 34.A cube has a volume of 6859 cubic cm. How long is each edge (in cm)?
  35. 35.A cube has a volume of 8 cubic cm. How long is each edge (in cm)?
  36. 36.Which of these is a perfect cube? (a) 43 (b) 30 (c) 27
  37. 37.A cube has a volume of 1331 cubic cm. How long is each edge (in cm)?
  38. 38.What is the smallest whole number by which 256 must be divided to get a perfect cube?
  39. 39.What is the smallest whole number by which 243 must be divided to get a perfect cube?
  40. 40.What is the smallest whole number by which 875 must be multiplied to get a perfect cube?

Answer key

  1. 14
  2. 1728
  3. 8
  4. 49
  5. 22
  6. 8
  7. 3
  8. 8
  9. 5
  10. 4
  11. 19
  12. 3375
  13. 4
  14. 49
  15. 216
  16. 23
  17. 125
  18. 1000
  19. 25
  20. 216
  21. 8
  22. 27
  23. 9
  24. 64
  25. 4913
  26. 1331
  27. 2197
  28. 6859
  29. 729
  30. 8
  31. 25
  32. 3
  33. 4
  34. 19
  35. 2
  36. 27
  37. 11
  38. 4
  39. 9
  40. 49

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