← Cubes and cube roots lesson New set →

Class 8 Maths Worksheet: Cubes and Cube Roots

Maths worksheets lesson 59: Cubes and cube roots · Set 573 · 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 big cube of edge 3 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  2. 2.What is the smallest whole number by which 1512 must be divided to get a perfect cube?
  3. 3.A cube has a volume of 4913 cubic cm. How long is each edge (in cm)?
  4. 4.What is the smallest whole number by which 243 must be multiplied to get a perfect cube?
  5. 5.Which of these is a perfect cube? (a) 674 (b) 693 (c) 512
  6. 6.What is ∛125? =
  7. 7.A cube has a volume of 1331 cubic cm. How long is each edge (in cm)?
  8. 8.What is ∛12167? =
  9. 9.A big cube of edge 18 cm is cut into small cubes of edge 3 cm. How many small cubes are there?
  10. 10.What is 8³? =
  11. 11.Which of these is a perfect cube? (a) 830 (b) 768 (c) 729
  12. 12.What is 7³? =
  13. 13.A cube has a volume of 6859 cubic cm. How long is each edge (in cm)?
  14. 14.What is 11³? =
  15. 15.A big cube of edge 6 cm is cut into small cubes of edge 3 cm. How many small cubes are there?
  16. 16.What is the smallest whole number by which 72 must be divided to get a perfect cube?
  17. 17.What is 20³? =
  18. 18.What is ∛8? =
  19. 19.Which of these is a perfect cube? (a) 154 (b) 126 (c) 125
  20. 20.What is 18³? =
  21. 21.A cube has a volume of 27 cubic cm. How long is each edge (in cm)?
  22. 22.What is 19³? =
  23. 23.What is 9³? =
  24. 24.What is ∛1331? =
  25. 25.Which of these is a perfect cube? (a) 3375 (b) 3986 (c) 3931
  26. 26.Which of these is a perfect cube? (a) 343 (b) 385 (c) 379
  27. 27.What is 16³? =
  28. 28.What is ∛15625? =
  29. 29.What is the smallest whole number by which 2 must be multiplied to get a perfect cube?
  30. 30.A big cube of edge 24 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  31. 31.A big cube of edge 5 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  32. 32.What is the smallest whole number by which 16 must be multiplied to get a perfect cube?
  33. 33.A big cube of edge 12 cm is cut into small cubes of edge 3 cm. How many small cubes are there?
  34. 34.A big cube of edge 10 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  35. 35.What is the smallest whole number by which 2 must be divided to get a perfect cube?
  36. 36.What is 12³? =
  37. 37.A cube has a volume of 343 cubic cm. How long is each edge (in cm)?
  38. 38.What is ∛343? =
  39. 39.What is ∛8000? =
  40. 40.What is 3³? =

Answer key

  1. 27
  2. 7
  3. 17
  4. 3
  5. 512
  6. 5
  7. 11
  8. 23
  9. 216
  10. 512
  11. 729
  12. 343
  13. 19
  14. 1331
  15. 8
  16. 9
  17. 8000
  18. 2
  19. 125
  20. 5832
  21. 3
  22. 6859
  23. 729
  24. 11
  25. 3375
  26. 343
  27. 4096
  28. 25
  29. 4
  30. 216
  31. 125
  32. 4
  33. 64
  34. 125
  35. 2
  36. 1728
  37. 7
  38. 7
  39. 20
  40. 27

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