← Cubes and cube roots lesson New set →

Class 8 Maths Worksheet: Cubes and Cube Roots

Maths worksheets lesson 59: Cubes and cube roots · Set 113 · 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 the smallest whole number by which 1323 must be divided to get a perfect cube?
  2. 2.What is ∛15625? =
  3. 3.Which of these is a perfect cube? (a) 2150 (b) 1728 (c) 2158
  4. 4.A cube has a volume of 2197 cubic cm. How long is each edge (in cm)?
  5. 5.What is 14³? =
  6. 6.What is the smallest whole number by which 243 must be multiplied to get a perfect cube?
  7. 7.A cube has a volume of 1728 cubic cm. How long is each edge (in cm)?
  8. 8.Which of these is a perfect cube? (a) 1147 (b) 1000 (c) 1274
  9. 9.What is 4³? =
  10. 10.Which of these is a perfect cube? (a) 168 (b) 185 (c) 125
  11. 11.What is the smallest whole number by which 375 must be divided to get a perfect cube?
  12. 12.What is ∛4913? =
  13. 13.What is 2³? =
  14. 14.What is ∛27? =
  15. 15.What is the smallest whole number by which 25 must be multiplied to get a perfect cube?
  16. 16.What is ∛6859? =
  17. 17.A cube has a volume of 729 cubic cm. How long is each edge (in cm)?
  18. 18.What is ∛9261? =
  19. 19.What is ∛8? =
  20. 20.What is ∛216? =
  21. 21.Which of these is a perfect cube? (a) 3770 (b) 3375 (c) 3513
  22. 22.A cube has a volume of 27 cubic cm. How long is each edge (in cm)?
  23. 23.What is the smallest whole number by which 7 must be multiplied to get a perfect cube?
  24. 24.A big cube of edge 3 cm is cut into small cubes of edge 1 cm. How many small cubes are there?
  25. 25.What is the smallest whole number by which 81 must be multiplied to get a perfect cube?
  26. 26.A big cube of edge 6 cm is cut into small cubes of edge 2 cm. How many small cubes are there?
  27. 27.A cube has a volume of 3375 cubic cm. How long is each edge (in cm)?
  28. 28.What is the smallest whole number by which 3 must be divided to get a perfect cube?
  29. 29.What is 11³? =
  30. 30.A cube has a volume of 1000 cubic cm. How long is each edge (in cm)?
  31. 31.A cube has a volume of 1331 cubic cm. How long is each edge (in cm)?
  32. 32.What is 17³? =
  33. 33.What is the smallest whole number by which 40 must be divided to get a perfect cube?
  34. 34.A cube has a volume of 2744 cubic cm. How long is each edge (in cm)?
  35. 35.Which of these is a perfect cube? (a) 1357 (b) 1558 (c) 1331
  36. 36.Which of these is a perfect cube? (a) 258 (b) 306 (c) 216
  37. 37.Which of these is a perfect cube? (a) 512 (b) 558 (c) 516
  38. 38.A cube has a volume of 343 cubic cm. How long is each edge (in cm)?
  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.A big cube of edge 15 cm is cut into small cubes of edge 3 cm. How many small cubes are there?

Answer key

  1. 49
  2. 25
  3. 1728
  4. 13
  5. 2744
  6. 3
  7. 12
  8. 1000
  9. 64
  10. 125
  11. 3
  12. 17
  13. 8
  14. 3
  15. 5
  16. 19
  17. 9
  18. 21
  19. 2
  20. 6
  21. 3375
  22. 3
  23. 49
  24. 27
  25. 9
  26. 27
  27. 15
  28. 3
  29. 1331
  30. 10
  31. 11
  32. 4913
  33. 5
  34. 14
  35. 1331
  36. 216
  37. 512
  38. 7
  39. 8
  40. 125

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