← Cubes and cube roots lesson New set →

Class 8 Maths Worksheet: Cubes and Cube Roots

Maths worksheets lesson 59: Cubes and cube roots · Set 928 · 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) 27 (b) 47 (c) 29
  2. 2.A cube has a volume of 1331 cubic cm. How long is each edge (in cm)?
  3. 3.What is ∛125? =
  4. 4.Which of these is a perfect cube? (a) 287 (b) 227 (c) 216
  5. 5.A cube has a volume of 1000 cubic cm. How long is each edge (in cm)?
  6. 6.What is 15³? =
  7. 7.A big cube of edge 5 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  8. 8.What is 4³? =
  9. 9.What is the smallest whole number by which 40 must be multiplied to get a perfect cube?
  10. 10.What is ∛27? =
  11. 11.A cube has a volume of 8000 cubic cm. How long is each edge (in cm)?
  12. 12.Which of these is a perfect cube? (a) 179 (b) 197 (c) 125
  13. 13.What is ∛1728? =
  14. 14.What is 9³? =
  15. 15.A big cube of edge 24 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  16. 16.Which of these is a perfect cube? (a) 73 (b) 64 (c) 79
  17. 17.What is ∛729? =
  18. 18.What is 3³? =
  19. 19.What is the smallest whole number by which 128 must be multiplied to get a perfect cube?
  20. 20.A big cube of edge 8 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  21. 21.A big cube of edge 20 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  22. 22.Which of these is a perfect cube? (a) 2089 (b) 1963 (c) 1728
  23. 23.What is 10³? =
  24. 24.A cube has a volume of 3375 cubic cm. How long is each edge (in cm)?
  25. 25.A big cube of edge 12 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  26. 26.A big cube of edge 2 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  27. 27.What is the smallest whole number by which 6125 must be multiplied to get a perfect cube?
  28. 28.What is ∛3375? =
  29. 29.Which of these is a perfect cube? (a) 488 (b) 390 (c) 343
  30. 30.A cube has a volume of 512 cubic cm. How long is each edge (in cm)?
  31. 31.What is the smallest whole number by which 1323 must be divided to get a perfect cube?
  32. 32.A cube has a volume of 2197 cubic cm. How long is each edge (in cm)?
  33. 33.What is 7³? =
  34. 34.What is the smallest whole number by which 4 must be divided to get a perfect cube?
  35. 35.What is 12³? =
  36. 36.Which of these is a perfect cube? (a) 3450 (b) 3614 (c) 3375
  37. 37.Which of these is a perfect cube? (a) 2305 (b) 2197 (c) 2379
  38. 38.A cube has a volume of 125 cubic cm. How long is each edge (in cm)?
  39. 39.What is the smallest whole number by which 72 must be multiplied to get a perfect cube?
  40. 40.A big cube of edge 10 cm is cut into small cubes of edge 2 cm. How many small cubes are there?

Answer key

  1. 27
  2. 11
  3. 5
  4. 216
  5. 10
  6. 3375
  7. 125
  8. 64
  9. 25
  10. 3
  11. 20
  12. 125
  13. 12
  14. 729
  15. 216
  16. 64
  17. 9
  18. 27
  19. 4
  20. 8
  21. 125
  22. 1728
  23. 1000
  24. 15
  25. 27
  26. 8
  27. 7
  28. 15
  29. 343
  30. 8
  31. 49
  32. 13
  33. 343
  34. 4
  35. 1728
  36. 3375
  37. 2197
  38. 5
  39. 3
  40. 125

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