← Cubes and cube roots lesson New set →

Class 8 Maths Worksheet: Cubes and Cube Roots

Maths worksheets lesson 59: Cubes and cube roots · Set 749 · 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 7³? =
  2. 2.Which of these is a perfect cube? (a) 187 (b) 177 (c) 125
  3. 3.What is 4³? =
  4. 4.What is ∛64? =
  5. 5.A big cube of edge 6 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  6. 6.What is the smallest whole number by which 200 must be divided to get a perfect cube?
  7. 7.What is 3³? =
  8. 8.A big cube of edge 6 cm is cut into small cubes of edge 3 cm. How many small cubes are there?
  9. 9.Which of these is a perfect cube? (a) 512 (b) 586 (c) 667
  10. 10.A big cube of edge 12 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  11. 11.A big cube of edge 20 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  12. 12.What is the smallest whole number by which 1512 must be divided to get a perfect cube?
  13. 13.Which of these is a perfect cube? (a) 216 (b) 230 (c) 235
  14. 14.A cube has a volume of 1728 cubic cm. How long is each edge (in cm)?
  15. 15.What is ∛512? =
  16. 16.Which of these is a perfect cube? (a) 2594 (b) 2197 (c) 2670
  17. 17.A big cube of edge 3 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  18. 18.A big cube of edge 6 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  19. 19.A cube has a volume of 6859 cubic cm. How long is each edge (in cm)?
  20. 20.What is ∛343? =
  21. 21.What is the smallest whole number by which 7 must be multiplied to get a perfect cube?
  22. 22.What is 5³? =
  23. 23.What is the smallest whole number by which 1600 must be multiplied to get a perfect cube?
  24. 24.What is 14³? =
  25. 25.What is 9³? =
  26. 26.A cube has a volume of 2197 cubic cm. How long is each edge (in cm)?
  27. 27.Which of these is a perfect cube? (a) 383 (b) 343 (c) 482
  28. 28.What is 12³? =
  29. 29.What is ∛15625? =
  30. 30.A big cube of edge 5 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  31. 31.What is ∛4096? =
  32. 32.Which of these is a perfect cube? (a) 54 (b) 27 (c) 46
  33. 33.What is 10³? =
  34. 34.What is the smallest whole number by which 3 must be multiplied to get a perfect cube?
  35. 35.What is ∛27? =
  36. 36.What is the smallest whole number by which 1600 must be divided to get a perfect cube?
  37. 37.What is 17³? =
  38. 38.What is the smallest whole number by which 3136 must be multiplied to get a perfect cube?
  39. 39.What is ∛125? =
  40. 40.What is 13³? =

Answer key

  1. 343
  2. 125
  3. 64
  4. 4
  5. 216
  6. 25
  7. 27
  8. 8
  9. 512
  10. 27
  11. 125
  12. 7
  13. 216
  14. 12
  15. 8
  16. 2197
  17. 27
  18. 27
  19. 19
  20. 7
  21. 49
  22. 125
  23. 5
  24. 2744
  25. 729
  26. 13
  27. 343
  28. 1728
  29. 25
  30. 125
  31. 16
  32. 27
  33. 1000
  34. 9
  35. 3
  36. 25
  37. 4913
  38. 7
  39. 5
  40. 2197

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