← Cubes and cube roots lesson New set →

Class 8 Maths Worksheet: Cubes and Cube Roots

Maths worksheets lesson 59: Cubes and cube roots · Set 379 · 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 18³? =
  2. 2.What is 14³? =
  3. 3.What is ∛5832? =
  4. 4.A big cube of edge 2 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  5. 5.A big cube of edge 12 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  6. 6.A cube has a volume of 216 cubic cm. How long is each edge (in cm)?
  7. 7.A cube has a volume of 729 cubic cm. How long is each edge (in cm)?
  8. 8.A cube has a volume of 512 cubic cm. How long is each edge (in cm)?
  9. 9.What is 2³? =
  10. 10.A cube has a volume of 8 cubic cm. How long is each edge (in cm)?
  11. 11.A cube has a volume of 343 cubic cm. How long is each edge (in cm)?
  12. 12.What is 10³? =
  13. 13.What is the smallest whole number by which 16 must be multiplied to get a perfect cube?
  14. 14.What is the smallest whole number by which 1944 must be multiplied to get a perfect cube?
  15. 15.A big cube of edge 8 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  16. 16.What is the smallest whole number by which 250 must be divided to get a perfect cube?
  17. 17.A big cube of edge 6 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  18. 18.What is 12³? =
  19. 19.What is 15³? =
  20. 20.What is the smallest whole number by which 432 must be multiplied to get a perfect cube?
  21. 21.What is ∛2744? =
  22. 22.What is ∛3375? =
  23. 23.What is ∛13824? =
  24. 24.A big cube of edge 5 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  25. 25.What is ∛216? =
  26. 26.Which of these is a perfect cube? (a) 1640 (b) 1414 (c) 1331
  27. 27.What is the smallest whole number by which 448 must be multiplied to get a perfect cube?
  28. 28.What is 3³? =
  29. 29.What is 17³? =
  30. 30.What is ∛1728? =
  31. 31.What is ∛1000? =
  32. 32.A big cube of edge 6 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  33. 33.Which of these is a perfect cube? (a) 49 (b) 27 (c) 38
  34. 34.A cube has a volume of 3375 cubic cm. How long is each edge (in cm)?
  35. 35.What is ∛4096? =
  36. 36.What is ∛2197? =
  37. 37.A cube has a volume of 64 cubic cm. How long is each edge (in cm)?
  38. 38.A big cube of edge 3 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  39. 39.A cube has a volume of 6859 cubic cm. How long is each edge (in cm)?
  40. 40.What is ∛125? =

Answer key

  1. 5832
  2. 2744
  3. 18
  4. 8
  5. 27
  6. 6
  7. 9
  8. 8
  9. 8
  10. 2
  11. 7
  12. 1000
  13. 4
  14. 3
  15. 64
  16. 2
  17. 27
  18. 1728
  19. 3375
  20. 4
  21. 14
  22. 15
  23. 24
  24. 125
  25. 6
  26. 1331
  27. 49
  28. 27
  29. 4913
  30. 12
  31. 10
  32. 216
  33. 27
  34. 15
  35. 16
  36. 13
  37. 4
  38. 27
  39. 19
  40. 5

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