← Cubes and cube roots lesson New set →

Class 8 Maths Worksheet: Cubes and Cube Roots

Maths worksheets lesson 59: Cubes and cube roots · Set 289 · 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) 658 (b) 529 (c) 512
  2. 2.What is 8³? =
  3. 3.What is the smallest whole number by which 375 must be divided to get a perfect cube?
  4. 4.Which of these is a perfect cube? (a) 3375 (b) 3414 (c) 3954
  5. 5.What is 13³? =
  6. 6.What is 2³? =
  7. 7.A big cube of edge 12 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  8. 8.What is 11³? =
  9. 9.What is 5³? =
  10. 10.A cube has a volume of 4913 cubic cm. How long is each edge (in cm)?
  11. 11.What is the smallest whole number by which 49 must be multiplied to get a perfect cube?
  12. 12.Which of these is a perfect cube? (a) 1034 (b) 1000 (c) 1043
  13. 13.What is the smallest whole number by which 10584 must be divided to get a perfect cube?
  14. 14.What is ∛512? =
  15. 15.What is the smallest whole number by which 1125 must be divided to get a perfect cube?
  16. 16.A big cube of edge 12 cm is cut into small cubes of edge 3 cm. How many small cubes are there?
  17. 17.A cube has a volume of 125 cubic cm. How long is each edge (in cm)?
  18. 18.What is 4³? =
  19. 19.A big cube of edge 16 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  20. 20.What is ∛13824? =
  21. 21.What is ∛1728? =
  22. 22.Which of these is a perfect cube? (a) 1331 (b) 1668 (c) 1432
  23. 23.A cube has a volume of 1728 cubic cm. How long is each edge (in cm)?
  24. 24.What is ∛15625? =
  25. 25.A cube has a volume of 27 cubic cm. How long is each edge (in cm)?
  26. 26.A big cube of edge 6 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  27. 27.What is ∛10648? =
  28. 28.What is the smallest whole number by which 576 must be multiplied to get a perfect cube?
  29. 29.What is the smallest whole number by which 256 must be multiplied to get a perfect cube?
  30. 30.Which of these is a perfect cube? (a) 216 (b) 217 (c) 255
  31. 31.A big cube of edge 5 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  32. 32.What is the smallest whole number by which 7 must be multiplied to get a perfect cube?
  33. 33.A big cube of edge 18 cm is cut into small cubes of edge 3 cm. How many small cubes are there?
  34. 34.What is the smallest whole number by which 192 must be multiplied to get a perfect cube?
  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) 846 (b) 729 (c) 844
  37. 37.What is the smallest whole number by which 1323 must be multiplied to get a perfect cube?
  38. 38.What is ∛125? =
  39. 39.What is the smallest whole number by which 6125 must be multiplied to get a perfect cube?
  40. 40.What is ∛8000? =

Answer key

  1. 512
  2. 512
  3. 3
  4. 3375
  5. 2197
  6. 8
  7. 216
  8. 1331
  9. 125
  10. 17
  11. 7
  12. 1000
  13. 49
  14. 8
  15. 9
  16. 64
  17. 5
  18. 64
  19. 64
  20. 24
  21. 12
  22. 1331
  23. 12
  24. 25
  25. 3
  26. 216
  27. 22
  28. 3
  29. 2
  30. 216
  31. 125
  32. 49
  33. 216
  34. 9
  35. 2
  36. 729
  37. 7
  38. 5
  39. 7
  40. 20

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