← Cubes and cube roots lesson New set →

Class 8 Maths Worksheet: Cubes and Cube Roots

Maths worksheets lesson 59: Cubes and cube roots · Set 830 · 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 8 cubic cm. How long is each edge (in cm)?
  2. 2.What is the smallest whole number by which 3136 must be divided to get a perfect cube?
  3. 3.Which of these is a perfect cube? (a) 1202 (b) 1000 (c) 1095
  4. 4.A big cube of edge 3 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  5. 5.A cube has a volume of 512 cubic cm. How long is each edge (in cm)?
  6. 6.A big cube of edge 24 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  7. 7.A big cube of edge 6 cm is cut into small cubes of edge 3 cm. How many small cubes are there?
  8. 8.A big cube of edge 18 cm is cut into small cubes of edge 3 cm. How many small cubes are there?
  9. 9.Which of these is a perfect cube? (a) 313 (b) 243 (c) 216
  10. 10.What is the smallest whole number by which 1080 must be multiplied to get a perfect cube?
  11. 11.Which of these is a perfect cube? (a) 2197 (b) 2249 (c) 2492
  12. 12.A cube has a volume of 27 cubic cm. How long is each edge (in cm)?
  13. 13.A big cube of edge 12 cm is cut into small cubes of edge 3 cm. How many small cubes are there?
  14. 14.What is ∛2744? =
  15. 15.What is the smallest whole number by which 7 must be multiplied to get a perfect cube?
  16. 16.What is the smallest whole number by which 243 must be multiplied to get a perfect cube?
  17. 17.What is 5³? =
  18. 18.What is the smallest whole number by which 10584 must be multiplied to get a perfect cube?
  19. 19.What is ∛27? =
  20. 20.Which of these is a perfect cube? (a) 178 (b) 125 (c) 149
  21. 21.Which of these is a perfect cube? (a) 543 (b) 512 (c) 640
  22. 22.What is ∛343? =
  23. 23.What is 4³? =
  24. 24.A big cube of edge 4 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  25. 25.What is the smallest whole number by which 16 must be multiplied to get a perfect cube?
  26. 26.A cube has a volume of 216 cubic cm. How long is each edge (in cm)?
  27. 27.What is the smallest whole number by which 648 must be divided to get a perfect cube?
  28. 28.A cube has a volume of 5832 cubic cm. How long is each edge (in cm)?
  29. 29.What is the smallest whole number by which 3 must be multiplied to get a perfect cube?
  30. 30.What is 10³? =
  31. 31.What is 20³? =
  32. 32.A big cube of edge 12 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  33. 33.What is the smallest whole number by which 675 must be multiplied to get a perfect cube?
  34. 34.What is ∛64? =
  35. 35.What is 16³? =
  36. 36.What is the smallest whole number by which 81 must be divided to get a perfect cube?
  37. 37.What is the smallest whole number by which 3 must be divided to get a perfect cube?
  38. 38.What is 3³? =
  39. 39.What is 17³? =
  40. 40.What is 19³? =

Answer key

  1. 2
  2. 49
  3. 1000
  4. 27
  5. 8
  6. 216
  7. 8
  8. 216
  9. 216
  10. 25
  11. 2197
  12. 3
  13. 64
  14. 14
  15. 49
  16. 3
  17. 125
  18. 7
  19. 3
  20. 125
  21. 512
  22. 7
  23. 64
  24. 8
  25. 4
  26. 6
  27. 3
  28. 18
  29. 9
  30. 1000
  31. 8000
  32. 216
  33. 5
  34. 4
  35. 4096
  36. 3
  37. 3
  38. 27
  39. 4913
  40. 6859

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