← Cubes and cube roots lesson New set →

Class 8 Maths Worksheet: Cubes and Cube Roots

Maths worksheets lesson 59: Cubes and cube roots · Set 481 · 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) 1857 (b) 1728 (c) 2146
  2. 2.Which of these is a perfect cube? (a) 2744 (b) 3124 (c) 3216
  3. 3.What is ∛729? =
  4. 4.Which of these is a perfect cube? (a) 343 (b) 487 (c) 474
  5. 5.A big cube of edge 12 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  6. 6.What is 11³? =
  7. 7.A cube has a volume of 1331 cubic cm. How long is each edge (in cm)?
  8. 8.What is the smallest whole number by which 32 must be multiplied to get a perfect cube?
  9. 9.A cube has a volume of 8000 cubic cm. How long is each edge (in cm)?
  10. 10.Which of these is a perfect cube? (a) 240 (b) 216 (c) 234
  11. 11.What is ∛9261? =
  12. 12.What is 6³? =
  13. 13.A cube has a volume of 2744 cubic cm. How long is each edge (in cm)?
  14. 14.What is ∛1331? =
  15. 15.What is the smallest whole number by which 375 must be multiplied to get a perfect cube?
  16. 16.What is the smallest whole number by which 40 must be divided to get a perfect cube?
  17. 17.Which of these is a perfect cube? (a) 65 (b) 64 (c) 68
  18. 18.A big cube of edge 12 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  19. 19.What is the smallest whole number by which 7 must be multiplied to get a perfect cube?
  20. 20.Which of these is a perfect cube? (a) 1163 (b) 1067 (c) 1000
  21. 21.What is ∛8? =
  22. 22.Which of these is a perfect cube? (a) 44 (b) 43 (c) 27
  23. 23.A big cube of edge 12 cm is cut into small cubes of edge 3 cm. How many small cubes are there?
  24. 24.A big cube of edge 20 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  25. 25.What is ∛12167? =
  26. 26.A big cube of edge 18 cm is cut into small cubes of edge 3 cm. How many small cubes are there?
  27. 27.A cube has a volume of 3375 cubic cm. How long is each edge (in cm)?
  28. 28.What is ∛1000? =
  29. 29.What is the smallest whole number by which 200 must be multiplied to get a perfect cube?
  30. 30.What is the smallest whole number by which 375 must be divided to get a perfect cube?
  31. 31.What is the smallest whole number by which 108 must be multiplied to get a perfect cube?
  32. 32.What is ∛27? =
  33. 33.A big cube of edge 16 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  34. 34.A big cube of edge 4 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  35. 35.Which of these is a perfect cube? (a) 3375 (b) 3823 (c) 3818
  36. 36.A big cube of edge 4 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  37. 37.What is 13³? =
  38. 38.What is 4³? =
  39. 39.What is ∛343? =
  40. 40.What is 10³? =

Answer key

  1. 1728
  2. 2744
  3. 9
  4. 343
  5. 216
  6. 1331
  7. 11
  8. 2
  9. 20
  10. 216
  11. 21
  12. 216
  13. 14
  14. 11
  15. 9
  16. 5
  17. 64
  18. 27
  19. 49
  20. 1000
  21. 2
  22. 27
  23. 64
  24. 125
  25. 23
  26. 216
  27. 15
  28. 10
  29. 5
  30. 3
  31. 2
  32. 3
  33. 64
  34. 8
  35. 3375
  36. 64
  37. 2197
  38. 64
  39. 7
  40. 1000

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