← Cubes and cube roots lesson New set →

Class 8 Maths Worksheet: Cubes and Cube Roots

Maths worksheets lesson 59: Cubes and cube roots · Set 910 · 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 10³? =
  2. 2.Which of these is a perfect cube? (a) 152 (b) 185 (c) 125
  3. 3.What is 9³? =
  4. 4.What is ∛1728? =
  5. 5.What is ∛343? =
  6. 6.Which of these is a perfect cube? (a) 1425 (b) 1597 (c) 1331
  7. 7.A cube has a volume of 8 cubic cm. How long is each edge (in cm)?
  8. 8.What is ∛27? =
  9. 9.What is the smallest whole number by which 5 must be multiplied to get a perfect cube?
  10. 10.What is the smallest whole number by which 375 must be divided to get a perfect cube?
  11. 11.A big cube of edge 3 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  12. 12.What is ∛12167? =
  13. 13.What is ∛729? =
  14. 14.A cube has a volume of 64 cubic cm. How long is each edge (in cm)?
  15. 15.A cube has a volume of 729 cubic cm. How long is each edge (in cm)?
  16. 16.What is ∛125? =
  17. 17.What is 17³? =
  18. 18.What is ∛13824? =
  19. 19.What is 5³? =
  20. 20.What is the smallest whole number by which 375 must be multiplied to get a perfect cube?
  21. 21.What is the smallest whole number by which 32 must be divided to get a perfect cube?
  22. 22.A cube has a volume of 1331 cubic cm. How long is each edge (in cm)?
  23. 23.What is ∛2744? =
  24. 24.What is 14³? =
  25. 25.What is the smallest whole number by which 500 must be divided to get a perfect cube?
  26. 26.What is the smallest whole number by which 16 must be divided to get a perfect cube?
  27. 27.Which of these is a perfect cube? (a) 109 (b) 64 (c) 70
  28. 28.Which of these is a perfect cube? (a) 216 (b) 258 (c) 228
  29. 29.A big cube of edge 12 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  30. 30.What is 18³? =
  31. 31.A cube has a volume of 5832 cubic cm. How long is each edge (in cm)?
  32. 32.What is 4³? =
  33. 33.What is the smallest whole number by which 3136 must be multiplied to get a perfect cube?
  34. 34.A cube has a volume of 1000 cubic cm. How long is each edge (in cm)?
  35. 35.A cube has a volume of 512 cubic cm. How long is each edge (in cm)?
  36. 36.What is the smallest whole number by which 1125 must be multiplied to get a perfect cube?
  37. 37.What is ∛6859? =
  38. 38.What is ∛2197? =
  39. 39.A cube has a volume of 1728 cubic cm. How long is each edge (in cm)?
  40. 40.A cube has a volume of 343 cubic cm. How long is each edge (in cm)?

Answer key

  1. 1000
  2. 125
  3. 729
  4. 12
  5. 7
  6. 1331
  7. 2
  8. 3
  9. 25
  10. 3
  11. 27
  12. 23
  13. 9
  14. 4
  15. 9
  16. 5
  17. 4913
  18. 24
  19. 125
  20. 9
  21. 4
  22. 11
  23. 14
  24. 2744
  25. 4
  26. 2
  27. 64
  28. 216
  29. 27
  30. 5832
  31. 18
  32. 64
  33. 7
  34. 10
  35. 8
  36. 3
  37. 19
  38. 13
  39. 12
  40. 7

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