← Cubes and cube roots lesson New set →

Class 8 Maths Worksheet: Cubes and Cube Roots

Maths worksheets lesson 59: Cubes and cube roots · Set 916 · 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.A big cube of edge 2 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  2. 2.A big cube of edge 6 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  3. 3.Which of these is a perfect cube? (a) 86 (b) 77 (c) 64
  4. 4.A cube has a volume of 125 cubic cm. How long is each edge (in cm)?
  5. 5.A cube has a volume of 8000 cubic cm. How long is each edge (in cm)?
  6. 6.A big cube of edge 4 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  7. 7.Which of these is a perfect cube? (a) 32 (b) 30 (c) 27
  8. 8.What is ∛8? =
  9. 9.What is 15³? =
  10. 10.What is 16³? =
  11. 11.A cube has a volume of 64 cubic cm. How long is each edge (in cm)?
  12. 12.What is ∛2744? =
  13. 13.A big cube of edge 18 cm is cut into small cubes of edge 3 cm. How many small cubes are there?
  14. 14.What is the smallest whole number by which 40 must be multiplied to get a perfect cube?
  15. 15.A cube has a volume of 343 cubic cm. How long is each edge (in cm)?
  16. 16.A big cube of edge 3 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  17. 17.A cube has a volume of 3375 cubic cm. How long is each edge (in cm)?
  18. 18.Which of these is a perfect cube? (a) 298 (b) 289 (c) 216
  19. 19.What is the smallest whole number by which 875 must be multiplied to get a perfect cube?
  20. 20.What is 7³? =
  21. 21.What is 10³? =
  22. 22.What is ∛10648? =
  23. 23.A big cube of edge 15 cm is cut into small cubes of edge 3 cm. How many small cubes are there?
  24. 24.A big cube of edge 16 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  25. 25.What is ∛3375? =
  26. 26.What is the smallest whole number by which 500 must be multiplied to get a perfect cube?
  27. 27.What is 9³? =
  28. 28.What is ∛1000? =
  29. 29.What is ∛8000? =
  30. 30.A cube has a volume of 1331 cubic cm. How long is each edge (in cm)?
  31. 31.A cube has a volume of 1000 cubic cm. How long is each edge (in cm)?
  32. 32.What is ∛6859? =
  33. 33.Which of these is a perfect cube? (a) 1172 (b) 1000 (c) 1140
  34. 34.What is the smallest whole number by which 432 must be divided to get a perfect cube?
  35. 35.What is the smallest whole number by which 5 must be divided to get a perfect cube?
  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 the smallest whole number by which 54 must be divided to get a perfect cube?
  38. 38.What is ∛4096? =
  39. 39.What is the smallest whole number by which 6125 must be divided to get a perfect cube?
  40. 40.What is 14³? =

Answer key

  1. 8
  2. 27
  3. 64
  4. 5
  5. 20
  6. 8
  7. 27
  8. 2
  9. 3375
  10. 4096
  11. 4
  12. 14
  13. 216
  14. 25
  15. 7
  16. 27
  17. 15
  18. 216
  19. 49
  20. 343
  21. 1000
  22. 22
  23. 125
  24. 64
  25. 15
  26. 2
  27. 729
  28. 10
  29. 20
  30. 11
  31. 10
  32. 19
  33. 1000
  34. 2
  35. 5
  36. 64
  37. 2
  38. 16
  39. 49
  40. 2744

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