← Cubes and cube roots lesson New set →

Class 8 Maths Worksheet: Cubes and Cube Roots

Maths worksheets lesson 59: Cubes and cube roots · Set 236 · 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.What is 15³? =
  2. 2.A cube has a volume of 216 cubic cm. How long is each edge (in cm)?
  3. 3.Which of these is a perfect cube? (a) 729 (b) 777 (c) 886
  4. 4.A cube has a volume of 343 cubic cm. How long is each edge (in cm)?
  5. 5.A big cube of edge 20 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  6. 6.A cube has a volume of 5832 cubic cm. How long is each edge (in cm)?
  7. 7.What is the smallest whole number by which 25 must be multiplied to get a perfect cube?
  8. 8.What is ∛3375? =
  9. 9.Which of these is a perfect cube? (a) 143 (b) 125 (c) 180
  10. 10.A cube has a volume of 8000 cubic cm. How long is each edge (in cm)?
  11. 11.What is 11³? =
  12. 12.A cube has a volume of 4913 cubic cm. How long is each edge (in cm)?
  13. 13.What is ∛2744? =
  14. 14.What is ∛4913? =
  15. 15.What is ∛15625? =
  16. 16.What is 8³? =
  17. 17.A big cube of edge 5 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  18. 18.What is 17³? =
  19. 19.A big cube of edge 2 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  20. 20.What is the smallest whole number by which 10584 must be divided to get a perfect cube?
  21. 21.What is ∛9261? =
  22. 22.A big cube of edge 9 cm is cut into small cubes of edge 3 cm. How many small cubes are there?
  23. 23.A cube has a volume of 1331 cubic cm. How long is each edge (in cm)?
  24. 24.What is the smallest whole number by which 189 must be multiplied to get a perfect cube?
  25. 25.A big cube of edge 6 cm is cut into small cubes of edge 3 cm. How many small cubes are there?
  26. 26.Which of these is a perfect cube? (a) 64 (b) 89 (c) 70
  27. 27.What is the smallest whole number by which 32 must be divided to get a perfect cube?
  28. 28.What is the smallest whole number by which 432 must be multiplied to get a perfect cube?
  29. 29.A cube has a volume of 2744 cubic cm. How long is each edge (in cm)?
  30. 30.A big cube of edge 6 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  31. 31.A big cube of edge 12 cm is cut into small cubes of edge 3 cm. How many small cubes are there?
  32. 32.What is the smallest whole number by which 6125 must be divided to get a perfect cube?
  33. 33.Which of these is a perfect cube? (a) 343 (b) 397 (c) 409
  34. 34.What is the smallest whole number by which 500 must be multiplied to get a perfect cube?
  35. 35.A cube has a volume of 2197 cubic cm. How long is each edge (in cm)?
  36. 36.What is 16³? =
  37. 37.A big cube of edge 8 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  38. 38.A cube has a volume of 64 cubic cm. How long is each edge (in cm)?
  39. 39.What is the smallest whole number by which 54 must be multiplied to get a perfect cube?
  40. 40.Which of these is a perfect cube? (a) 3375 (b) 4046 (c) 3439

Answer key

  1. 3375
  2. 6
  3. 729
  4. 7
  5. 125
  6. 18
  7. 5
  8. 15
  9. 125
  10. 20
  11. 1331
  12. 17
  13. 14
  14. 17
  15. 25
  16. 512
  17. 125
  18. 4913
  19. 8
  20. 49
  21. 21
  22. 27
  23. 11
  24. 49
  25. 8
  26. 64
  27. 4
  28. 4
  29. 14
  30. 216
  31. 64
  32. 49
  33. 343
  34. 2
  35. 13
  36. 4096
  37. 8
  38. 4
  39. 4
  40. 3375

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