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Class 8 Maths Worksheet: Squares and Square Roots

Maths worksheets lesson 58: Squares and square roots · Set 325 · 40 sums
TalentJR

The method (Pairs make squares): Square: n × n. Quick way: (a + b)² = a² + 2ab + b², e.g. 42² = 1600 + 160 + 4. Square root: the number that times itself gives the square; a square ending in 4 has a root ending in 2 or 8. Make a perfect square: break into primes; multiply (or divide) by the prime left without a partner. 1 + 3 + 5 + … (n odd numbers) = n². Between n² and (n + 1)² there are 2n whole numbers.

NameDateTime takenScore ___ / 40
  1. 1.What is the smallest whole number by which 252 must be divided to get a perfect square?
  2. 2.What is the sum of the first 16 odd numbers (1 + 3 + 5 + …)?
  3. 3.What is the sum of the first 27 odd numbers (1 + 3 + 5 + …)?
  4. 4.What is 31²? =
  5. 5.What is 58²? =
  6. 6.How many whole numbers lie between 34² and 35²?
  7. 7.What is 19²? =
  8. 8.What is √3136? =
  9. 9.A square garden has an area of 1089 square m. How long is each side (in m)?
  10. 10.Which of these is a perfect square? (a) 790 (b) 784 (c) 804
  11. 11.How many whole numbers lie between 29² and 30²?
  12. 12.What is the sum of the first 10 odd numbers (1 + 3 + 5 + …)?
  13. 13.What is the smallest whole number by which 63 must be multiplied to get a perfect square?
  14. 14.What is 81²? =
  15. 15.What is √4225? =
  16. 16.A square garden has an area of 2401 square m. How long is each side (in m)?
  17. 17.What is √400? =
  18. 18.What is the sum of the first 24 odd numbers (1 + 3 + 5 + …)?
  19. 19.What is 18²? =
  20. 20.Which of these is a perfect square? (a) 694 (b) 709 (c) 676
  21. 21.What is the sum of the first 23 odd numbers (1 + 3 + 5 + …)?
  22. 22.What is the smallest whole number by which 192 must be multiplied to get a perfect square?
  23. 23.What is √4489? =
  24. 24.What is √3364? =
  25. 25.What is the smallest whole number by which 360 must be divided to get a perfect square?
  26. 26.Which of these is a perfect square? (a) 900 (b) 950 (c) 920
  27. 27.What is √4761? =
  28. 28.What is the sum of the first 22 odd numbers (1 + 3 + 5 + …)?
  29. 29.What is the sum of the first 28 odd numbers (1 + 3 + 5 + …)?
  30. 30.What is 24²? =
  31. 31.What is √1849? =
  32. 32.How many whole numbers lie between 22² and 23²?
  33. 33.Which of these is a perfect square? (a) 1107 (b) 1089 (c) 1108
  34. 34.What is the smallest whole number by which 832 must be multiplied to get a perfect square?
  35. 35.How many whole numbers lie between 18² and 19²?
  36. 36.How many whole numbers lie between 26² and 27²?
  37. 37.How many whole numbers lie between 27² and 28²?
  38. 38.What is 60²? =
  39. 39.A square garden has an area of 36 square m. How long is each side (in m)?
  40. 40.What is 75²? =

Answer key

  1. 7
  2. 256
  3. 729
  4. 961
  5. 3364
  6. 68
  7. 361
  8. 56
  9. 33
  10. 784
  11. 58
  12. 100
  13. 7
  14. 6561
  15. 65
  16. 49
  17. 20
  18. 576
  19. 324
  20. 676
  21. 529
  22. 3
  23. 67
  24. 58
  25. 10
  26. 900
  27. 69
  28. 484
  29. 784
  30. 576
  31. 43
  32. 44
  33. 1089
  34. 13
  35. 36
  36. 52
  37. 54
  38. 3600
  39. 6
  40. 5625

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