← Cubes and cube roots lesson New set →

Class 8 Maths Worksheet: Cubes and Cube Roots

Maths worksheets lesson 59: Cubes and cube roots · Set 986 · 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 cube has a volume of 1728 cubic cm. How long is each edge (in cm)?
  2. 2.A cube has a volume of 6859 cubic cm. How long is each edge (in cm)?
  3. 3.Which of these is a perfect cube? (a) 1410 (b) 1331 (c) 1438
  4. 4.What is 11³? =
  5. 5.What is ∛1728? =
  6. 6.What is ∛8? =
  7. 7.What is ∛216? =
  8. 8.What is the smallest whole number by which 192 must be multiplied to get a perfect cube?
  9. 9.What is 13³? =
  10. 10.Which of these is a perfect cube? (a) 3159 (b) 2744 (c) 3109
  11. 11.What is ∛2744? =
  12. 12.What is ∛4913? =
  13. 13.A big cube of edge 12 cm is cut into small cubes of edge 4 cm. How many small cubes are there?
  14. 14.What is the smallest whole number by which 1125 must be multiplied to get a perfect cube?
  15. 15.A cube has a volume of 2197 cubic cm. How long is each edge (in cm)?
  16. 16.A big cube of edge 6 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  17. 17.A big cube of edge 12 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  18. 18.What is 17³? =
  19. 19.What is 5³? =
  20. 20.What is the smallest whole number by which 3125 must be multiplied to get a perfect cube?
  21. 21.What is the smallest whole number by which 189 must be multiplied to get a perfect cube?
  22. 22.What is 9³? =
  23. 23.What is the smallest whole number by which 3136 must be multiplied to get a perfect cube?
  24. 24.Which of these is a perfect cube? (a) 98 (b) 109 (c) 64
  25. 25.What is ∛5832? =
  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 ∛343? =
  28. 28.What is 2³? =
  29. 29.A big cube of edge 3 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  30. 30.What is the smallest whole number by which 1323 must be divided to get a perfect cube?
  31. 31.A cube has a volume of 4096 cubic cm. How long is each edge (in cm)?
  32. 32.A cube has a volume of 2744 cubic cm. How long is each edge (in cm)?
  33. 33.Which of these is a perfect cube? (a) 526 (b) 616 (c) 512
  34. 34.A cube has a volume of 64 cubic cm. How long is each edge (in cm)?
  35. 35.What is the smallest whole number by which 56 must be multiplied to get a perfect cube?
  36. 36.What is 20³? =
  37. 37.What is the smallest whole number by which 1600 must be multiplied to get a perfect cube?
  38. 38.Which of these is a perfect cube? (a) 293 (b) 250 (c) 216
  39. 39.A cube has a volume of 3375 cubic cm. How long is each edge (in cm)?
  40. 40.Which of these is a perfect cube? (a) 909 (b) 737 (c) 729

Answer key

  1. 12
  2. 19
  3. 1331
  4. 1331
  5. 12
  6. 2
  7. 6
  8. 9
  9. 2197
  10. 2744
  11. 14
  12. 17
  13. 27
  14. 3
  15. 13
  16. 216
  17. 216
  18. 4913
  19. 125
  20. 5
  21. 49
  22. 729
  23. 7
  24. 64
  25. 18
  26. 8
  27. 7
  28. 8
  29. 27
  30. 49
  31. 16
  32. 14
  33. 512
  34. 4
  35. 49
  36. 8000
  37. 5
  38. 216
  39. 15
  40. 729

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