← Cubes and cube roots lesson New set →

Class 8 Maths Worksheet: Cubes and Cube Roots

Maths worksheets lesson 59: Cubes and cube roots · Set 449 · 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 ∛13824? =
  2. 2.A big cube of edge 8 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  3. 3.What is the smallest whole number by which 648 must be multiplied to get a perfect cube?
  4. 4.What is ∛10648? =
  5. 5.What is 4³? =
  6. 6.A cube has a volume of 343 cubic cm. How long is each edge (in cm)?
  7. 7.A big cube of edge 16 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  8. 8.A cube has a volume of 4096 cubic cm. How long is each edge (in cm)?
  9. 9.What is the smallest whole number by which 200 must be divided to get a perfect cube?
  10. 10.What is the smallest whole number by which 135 must be divided to get a perfect cube?
  11. 11.What is the smallest whole number by which 2 must be divided to get a perfect cube?
  12. 12.What is 19³? =
  13. 13.A big cube of edge 3 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  14. 14.What is ∛4913? =
  15. 15.What is ∛6859? =
  16. 16.What is ∛5832? =
  17. 17.A cube has a volume of 216 cubic cm. How long is each edge (in cm)?
  18. 18.What is 16³? =
  19. 19.What is the smallest whole number by which 81 must be multiplied to get a perfect cube?
  20. 20.A big cube of edge 10 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  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.A big cube of edge 18 cm is cut into small cubes of edge 3 cm. How many small cubes are there?
  23. 23.What is the smallest whole number by which 192 must be multiplied to get a perfect cube?
  24. 24.What is the smallest whole number by which 625 must be multiplied to get a perfect cube?
  25. 25.What is 5³? =
  26. 26.What is ∛343? =
  27. 27.A big cube of edge 6 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  28. 28.A cube has a volume of 64 cubic cm. How long is each edge (in cm)?
  29. 29.A cube has a volume of 729 cubic cm. How long is each edge (in cm)?
  30. 30.What is ∛2197? =
  31. 31.Which of these is a perfect cube? (a) 3375 (b) 3785 (c) 3515
  32. 32.What is ∛1728? =
  33. 33.What is 18³? =
  34. 34.A big cube of edge 5 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  35. 35.What is the smallest whole number by which 1600 must be divided to get a perfect cube?
  36. 36.A cube has a volume of 125 cubic cm. How long is each edge (in cm)?
  37. 37.A big cube of edge 24 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  38. 38.Which of these is a perfect cube? (a) 1741 (b) 1728 (c) 1988
  39. 39.A big cube of edge 4 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  40. 40.A cube has a volume of 27 cubic cm. How long is each edge (in cm)?

Answer key

  1. 24
  2. 8
  3. 9
  4. 22
  5. 64
  6. 7
  7. 64
  8. 16
  9. 25
  10. 5
  11. 2
  12. 6859
  13. 27
  14. 17
  15. 19
  16. 18
  17. 6
  18. 4096
  19. 9
  20. 125
  21. 64
  22. 216
  23. 9
  24. 25
  25. 125
  26. 7
  27. 27
  28. 4
  29. 9
  30. 13
  31. 3375
  32. 12
  33. 5832
  34. 125
  35. 25
  36. 5
  37. 216
  38. 1728
  39. 64
  40. 3

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