← Cubes and cube roots lesson New set →

Class 8 Maths Worksheet: Cubes and Cube Roots

Maths worksheets lesson 59: Cubes and cube roots · Set 615 · 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) 216 (b) 303 (c) 221
  2. 2.A big cube of edge 3 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  3. 3.A cube has a volume of 8000 cubic cm. How long is each edge (in cm)?
  4. 4.What is the smallest whole number by which 6125 must be divided to get a perfect cube?
  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 5³? =
  7. 7.A big cube of edge 5 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  8. 8.What is the smallest whole number by which 448 must be multiplied to get a perfect cube?
  9. 9.Which of these is a perfect cube? (a) 1635 (b) 1543 (c) 1331
  10. 10.What is ∛2197? =
  11. 11.What is 2³? =
  12. 12.A big cube of edge 2 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  13. 13.Which of these is a perfect cube? (a) 185 (b) 125 (c) 133
  14. 14.A cube has a volume of 1728 cubic cm. How long is each edge (in cm)?
  15. 15.Which of these is a perfect cube? (a) 436 (b) 392 (c) 343
  16. 16.What is 9³? =
  17. 17.What is the smallest whole number by which 1600 must be divided to get a perfect cube?
  18. 18.A big cube of edge 4 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  19. 19.What is ∛1331? =
  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.Which of these is a perfect cube? (a) 86 (b) 90 (c) 64
  22. 22.What is the smallest whole number by which 875 must be divided to get a perfect cube?
  23. 23.What is ∛8000? =
  24. 24.Which of these is a perfect cube? (a) 835 (b) 972 (c) 729
  25. 25.What is 8³? =
  26. 26.What is ∛216? =
  27. 27.A big cube of edge 16 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  28. 28.What is 20³? =
  29. 29.What is ∛1728? =
  30. 30.What is 16³? =
  31. 31.A cube has a volume of 125 cubic cm. How long is each edge (in cm)?
  32. 32.A big cube of edge 20 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  33. 33.What is ∛343? =
  34. 34.What is 4³? =
  35. 35.What is the smallest whole number by which 49 must be divided to get a perfect cube?
  36. 36.What is the smallest whole number by which 648 must be multiplied to get a perfect cube?
  37. 37.What is 15³? =
  38. 38.A big cube of edge 6 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  39. 39.Which of these is a perfect cube? (a) 2821 (b) 2762 (c) 2744
  40. 40.What is ∛1000? =

Answer key

  1. 216
  2. 27
  3. 20
  4. 49
  5. 216
  6. 125
  7. 125
  8. 49
  9. 1331
  10. 13
  11. 8
  12. 8
  13. 125
  14. 12
  15. 343
  16. 729
  17. 25
  18. 64
  19. 11
  20. 27
  21. 64
  22. 7
  23. 20
  24. 729
  25. 512
  26. 6
  27. 64
  28. 8000
  29. 12
  30. 4096
  31. 5
  32. 125
  33. 7
  34. 64
  35. 49
  36. 9
  37. 3375
  38. 27
  39. 2744
  40. 10

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