← Cubes and cube roots lesson New set →

Class 8 Maths Worksheet: Cubes and Cube Roots

Maths worksheets lesson 59: Cubes and cube roots · Set 38 · 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.Which of these is a perfect cube? (a) 941 (b) 729 (c) 944
  2. 2.What is 7³? =
  3. 3.A big cube of edge 12 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  4. 4.What is ∛343? =
  5. 5.A cube has a volume of 512 cubic cm. How long is each edge (in cm)?
  6. 6.What is 3³? =
  7. 7.Which of these is a perfect cube? (a) 64 (b) 72 (c) 69
  8. 8.A big cube of edge 8 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  9. 9.A cube has a volume of 1728 cubic cm. How long is each edge (in cm)?
  10. 10.What is ∛729? =
  11. 11.What is the smallest whole number by which 432 must be divided to get a perfect cube?
  12. 12.What is 5³? =
  13. 13.What is the smallest whole number by which 16 must be divided to get a perfect cube?
  14. 14.A cube has a volume of 6859 cubic cm. How long is each edge (in cm)?
  15. 15.A cube has a volume of 125 cubic cm. How long is each edge (in cm)?
  16. 16.What is the smallest whole number by which 625 must be multiplied to get a perfect cube?
  17. 17.What is ∛27? =
  18. 18.What is 17³? =
  19. 19.A cube has a volume of 27 cubic cm. How long is each edge (in cm)?
  20. 20.What is 9³? =
  21. 21.A big cube of edge 3 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  22. 22.What is ∛1331? =
  23. 23.What is the smallest whole number by which 108 must be multiplied to get a perfect cube?
  24. 24.What is 4³? =
  25. 25.A big cube of edge 6 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  26. 26.What is 11³? =
  27. 27.Which of these is a perfect cube? (a) 1664 (b) 1672 (c) 1331
  28. 28.A big cube of edge 12 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  29. 29.Which of these is a perfect cube? (a) 125 (b) 191 (c) 151
  30. 30.Which of these is a perfect cube? (a) 1959 (b) 2074 (c) 1728
  31. 31.A big cube of edge 8 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  32. 32.A big cube of edge 4 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  33. 33.What is the smallest whole number by which 56 must be divided to get a perfect cube?
  34. 34.Which of these is a perfect cube? (a) 1015 (b) 1000 (c) 1299
  35. 35.What is ∛12167? =
  36. 36.What is the smallest whole number by which 375 must be divided to get a perfect cube?
  37. 37.Which of these is a perfect cube? (a) 575 (b) 588 (c) 512
  38. 38.A cube has a volume of 216 cubic cm. How long is each edge (in cm)?
  39. 39.What is the smallest whole number by which 1512 must be multiplied to get a perfect cube?
  40. 40.A big cube of edge 24 cm is cut into small cubes of edge 4 cm. How many small cubes are there?

Answer key

  1. 729
  2. 343
  3. 27
  4. 7
  5. 8
  6. 27
  7. 64
  8. 8
  9. 12
  10. 9
  11. 2
  12. 125
  13. 2
  14. 19
  15. 5
  16. 25
  17. 3
  18. 4913
  19. 3
  20. 729
  21. 27
  22. 11
  23. 2
  24. 64
  25. 27
  26. 1331
  27. 1331
  28. 216
  29. 125
  30. 1728
  31. 64
  32. 64
  33. 7
  34. 1000
  35. 23
  36. 3
  37. 512
  38. 6
  39. 49
  40. 216

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