← Cubes and cube roots lesson New set →

Class 8 Maths Worksheet: Cubes and Cube Roots

Maths worksheets lesson 59: Cubes and cube roots · Set 900 · 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 cube has a volume of 27 cubic cm. How long is each edge (in cm)?
  2. 2.Which of these is a perfect cube? (a) 629 (b) 535 (c) 512
  3. 3.What is 11³? =
  4. 4.What is ∛125? =
  5. 5.A cube has a volume of 2744 cubic cm. How long is each edge (in cm)?
  6. 6.What is the smallest whole number by which 5 must be divided to get a perfect cube?
  7. 7.What is the smallest whole number by which 16 must be divided to get a perfect cube?
  8. 8.What is 5³? =
  9. 9.A big cube of edge 3 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  10. 10.What is ∛1728? =
  11. 11.Which of these is a perfect cube? (a) 1038 (b) 1000 (c) 1112
  12. 12.A big cube of edge 18 cm is cut into small cubes of edge 3 cm. How many small cubes are there?
  13. 13.What is the smallest whole number by which 25 must be multiplied to get a perfect cube?
  14. 14.What is the smallest whole number by which 189 must be multiplied to get a perfect cube?
  15. 15.Which of these is a perfect cube? (a) 2937 (b) 2852 (c) 2744
  16. 16.A cube has a volume of 2197 cubic cm. How long is each edge (in cm)?
  17. 17.A cube has a volume of 6859 cubic cm. How long is each edge (in cm)?
  18. 18.What is ∛6859? =
  19. 19.What is the smallest whole number by which 500 must be multiplied to get a perfect cube?
  20. 20.What is the smallest whole number by which 250 must be multiplied to get a perfect cube?
  21. 21.What is 16³? =
  22. 22.Which of these is a perfect cube? (a) 268 (b) 238 (c) 216
  23. 23.A big cube of edge 4 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  24. 24.A cube has a volume of 343 cubic cm. How long is each edge (in cm)?
  25. 25.What is ∛1331? =
  26. 26.A big cube of edge 12 cm is cut into small cubes of edge 3 cm. How many small cubes are there?
  27. 27.A big cube of edge 15 cm is cut into small cubes of edge 3 cm. How many small cubes are there?
  28. 28.What is 18³? =
  29. 29.What is the smallest whole number by which 320 must be divided to get a perfect cube?
  30. 30.Which of these is a perfect cube? (a) 64 (b) 75 (c) 69
  31. 31.What is 3³? =
  32. 32.What is 13³? =
  33. 33.A cube has a volume of 8 cubic cm. How long is each edge (in cm)?
  34. 34.What is the smallest whole number by which 25 must be divided to get a perfect cube?
  35. 35.A big cube of edge 16 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  36. 36.What is ∛2197? =
  37. 37.Which of these is a perfect cube? (a) 2197 (b) 2647 (c) 2288
  38. 38.What is ∛5832? =
  39. 39.What is the smallest whole number by which 3136 must be divided to get a perfect cube?
  40. 40.What is 2³? =

Answer key

  1. 3
  2. 512
  3. 1331
  4. 5
  5. 14
  6. 5
  7. 2
  8. 125
  9. 27
  10. 12
  11. 1000
  12. 216
  13. 5
  14. 49
  15. 2744
  16. 13
  17. 19
  18. 19
  19. 2
  20. 4
  21. 4096
  22. 216
  23. 8
  24. 7
  25. 11
  26. 64
  27. 125
  28. 5832
  29. 5
  30. 64
  31. 27
  32. 2197
  33. 2
  34. 25
  35. 64
  36. 13
  37. 2197
  38. 18
  39. 49
  40. 8

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