← Cubes and cube roots lesson New set →

Class 8 Maths Worksheet: Cubes and Cube Roots

Maths worksheets lesson 59: Cubes and cube roots · Set 795 · 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 the smallest whole number by which 200 must be divided to get a perfect cube?
  2. 2.What is 9³? =
  3. 3.A big cube of edge 15 cm is cut into small cubes of edge 3 cm. How many small cubes are there?
  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.Which of these is a perfect cube? (a) 107 (b) 71 (c) 64
  7. 7.A cube has a volume of 2744 cubic cm. How long is each edge (in cm)?
  8. 8.Which of these is a perfect cube? (a) 2470 (b) 2689 (c) 2197
  9. 9.A big cube of edge 9 cm is cut into small cubes of edge 3 cm. How many small cubes are there?
  10. 10.What is 10³? =
  11. 11.What is 19³? =
  12. 12.What is 8³? =
  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 5³? =
  15. 15.What is 2³? =
  16. 16.What is the smallest whole number by which 108 must be multiplied to get a perfect cube?
  17. 17.What is 4³? =
  18. 18.What is 13³? =
  19. 19.What is 7³? =
  20. 20.A big cube of edge 12 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  21. 21.What is ∛729? =
  22. 22.A cube has a volume of 4913 cubic cm. How long is each edge (in cm)?
  23. 23.What is ∛8000? =
  24. 24.A cube has a volume of 5832 cubic cm. How long is each edge (in cm)?
  25. 25.A cube has a volume of 3375 cubic cm. How long is each edge (in cm)?
  26. 26.What is the smallest whole number by which 5 must be divided to get a perfect cube?
  27. 27.What is ∛12167? =
  28. 28.A big cube of edge 8 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  29. 29.What is ∛15625? =
  30. 30.A big cube of edge 16 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  31. 31.Which of these is a perfect cube? (a) 1000 (b) 1222 (c) 1255
  32. 32.Which of these is a perfect cube? (a) 310 (b) 309 (c) 216
  33. 33.What is 3³? =
  34. 34.What is the smallest whole number by which 1323 must be multiplied to get a perfect cube?
  35. 35.What is 18³? =
  36. 36.What is the smallest whole number by which 54 must be multiplied to get a perfect cube?
  37. 37.A cube has a volume of 125 cubic cm. How long is each edge (in cm)?
  38. 38.A big cube of edge 24 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  39. 39.A cube has a volume of 216 cubic cm. How long is each edge (in cm)?
  40. 40.A cube has a volume of 8000 cubic cm. How long is each edge (in cm)?

Answer key

  1. 25
  2. 729
  3. 125
  4. 3
  5. 125
  6. 64
  7. 14
  8. 2197
  9. 27
  10. 1000
  11. 6859
  12. 512
  13. 27
  14. 125
  15. 8
  16. 2
  17. 64
  18. 2197
  19. 343
  20. 27
  21. 9
  22. 17
  23. 20
  24. 18
  25. 15
  26. 5
  27. 23
  28. 8
  29. 25
  30. 64
  31. 1000
  32. 216
  33. 27
  34. 7
  35. 5832
  36. 4
  37. 5
  38. 216
  39. 6
  40. 20

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