← Cubes and cube roots lesson New set →

Class 8 Maths Worksheet: Cubes and Cube Roots

Maths worksheets lesson 59: Cubes and cube roots · Set 169 · 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) 343 (b) 374 (c) 454
  2. 2.Which of these is a perfect cube? (a) 1686 (b) 1331 (c) 1397
  3. 3.Which of these is a perfect cube? (a) 561 (b) 518 (c) 512
  4. 4.A cube has a volume of 216 cubic cm. How long is each edge (in cm)?
  5. 5.What is the smallest whole number by which 56 must be multiplied to get a perfect cube?
  6. 6.Which of these is a perfect cube? (a) 268 (b) 216 (c) 304
  7. 7.What is ∛729? =
  8. 8.What is ∛3375? =
  9. 9.What is ∛6859? =
  10. 10.What is the smallest whole number by which 72 must be divided to get a perfect cube?
  11. 11.What is 15³? =
  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 13³? =
  14. 14.What is ∛15625? =
  15. 15.What is the smallest whole number by which 1944 must be multiplied to get a perfect cube?
  16. 16.Which of these is a perfect cube? (a) 1110 (b) 1244 (c) 1000
  17. 17.What is 3³? =
  18. 18.A big cube of edge 2 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  19. 19.What is ∛8? =
  20. 20.Which of these is a perfect cube? (a) 2132 (b) 1728 (c) 1761
  21. 21.What is the smallest whole number by which 24 must be multiplied to get a perfect cube?
  22. 22.What is 6³? =
  23. 23.What is 5³? =
  24. 24.What is ∛1331? =
  25. 25.What is the smallest whole number by which 1323 must be divided to get a perfect cube?
  26. 26.What is the smallest whole number by which 256 must be divided to get a perfect cube?
  27. 27.What is ∛12167? =
  28. 28.What is the smallest whole number by which 7 must be divided to get a perfect cube?
  29. 29.What is 7³? =
  30. 30.What is the smallest whole number by which 1512 must be divided to get a perfect cube?
  31. 31.What is 16³? =
  32. 32.What is ∛5832? =
  33. 33.Which of these is a perfect cube? (a) 3922 (b) 3375 (c) 3591
  34. 34.A big cube of edge 12 cm is cut into small cubes of edge 3 cm. How many small cubes are there?
  35. 35.A big cube of edge 9 cm is cut into small cubes of edge 3 cm. How many small cubes are there?
  36. 36.A big cube of edge 8 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  37. 37.What is ∛64? =
  38. 38.What is the smallest whole number by which 5 must be multiplied to get a perfect cube?
  39. 39.A big cube of edge 4 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  40. 40.What is ∛4096? =

Answer key

  1. 343
  2. 1331
  3. 512
  4. 6
  5. 49
  6. 216
  7. 9
  8. 15
  9. 19
  10. 9
  11. 3375
  12. 216
  13. 2197
  14. 25
  15. 3
  16. 1000
  17. 27
  18. 8
  19. 2
  20. 1728
  21. 9
  22. 216
  23. 125
  24. 11
  25. 49
  26. 4
  27. 23
  28. 7
  29. 343
  30. 7
  31. 4096
  32. 18
  33. 3375
  34. 64
  35. 27
  36. 64
  37. 4
  38. 25
  39. 8
  40. 16

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