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Class 8 Maths Worksheet: Squares and Square Roots

Maths worksheets lesson 58: Squares and square roots · Set 388 · 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 √4900? =
  2. 2.What is 95²? =
  3. 3.A square garden has an area of 121 square m. How long is each side (in m)?
  4. 4.A square garden has an area of 25 square m. How long is each side (in m)?
  5. 5.A square garden has an area of 1024 square m. How long is each side (in m)?
  6. 6.What is the smallest whole number by which 243 must be multiplied to get a perfect square?
  7. 7.How many whole numbers lie between 50² and 51²?
  8. 8.What is the smallest whole number by which 405 must be multiplied to get a perfect square?
  9. 9.How many whole numbers lie between 10² and 11²?
  10. 10.Which of these is a perfect square? (a) 482 (b) 445 (c) 441
  11. 11.Which of these is a perfect square? (a) 1089 (b) 1121 (c) 1096
  12. 12.What is the sum of the first 6 odd numbers (1 + 3 + 5 + …)?
  13. 13.Which of these is a perfect square? (a) 675 (b) 625 (c) 657
  14. 14.What is 65²? =
  15. 15.What is 57²? =
  16. 16.What is 11²? =
  17. 17.How many whole numbers lie between 35² and 36²?
  18. 18.How many whole numbers lie between 36² and 37²?
  19. 19.What is 83²? =
  20. 20.Which of these is a perfect square? (a) 1085 (b) 1046 (c) 1024
  21. 21.A square garden has an area of 841 square m. How long is each side (in m)?
  22. 22.How many whole numbers lie between 9² and 10²?
  23. 23.What is the sum of the first 8 odd numbers (1 + 3 + 5 + …)?
  24. 24.Which of these is a perfect square? (a) 487 (b) 516 (c) 484
  25. 25.What is 43²? =
  26. 26.What is √5625? =
  27. 27.What is √3364? =
  28. 28.What is the smallest whole number by which 72 must be multiplied to get a perfect square?
  29. 29.What is 31²? =
  30. 30.Which of these is a perfect square? (a) 178 (b) 169 (c) 174
  31. 31.What is 19²? =
  32. 32.What is √9216? =
  33. 33.What is √3969? =
  34. 34.What is the smallest whole number by which 50 must be multiplied to get a perfect square?
  35. 35.What is 37²? =
  36. 36.What is √4489? =
  37. 37.A square garden has an area of 2209 square m. How long is each side (in m)?
  38. 38.What is 66²? =
  39. 39.What is √841? =
  40. 40.How many whole numbers lie between 48² and 49²?

Answer key

  1. 70
  2. 9025
  3. 11
  4. 5
  5. 32
  6. 3
  7. 100
  8. 5
  9. 20
  10. 441
  11. 1089
  12. 36
  13. 625
  14. 4225
  15. 3249
  16. 121
  17. 70
  18. 72
  19. 6889
  20. 1024
  21. 29
  22. 18
  23. 64
  24. 484
  25. 1849
  26. 75
  27. 58
  28. 2
  29. 961
  30. 169
  31. 361
  32. 96
  33. 63
  34. 2
  35. 1369
  36. 67
  37. 47
  38. 4356
  39. 29
  40. 96

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