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Class 8 Maths Worksheet: Squares and Square Roots

Maths worksheets lesson 58: Squares and square roots · Set 466 · 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.Which of these is a perfect square? (a) 303 (b) 289 (c) 302
  2. 2.Which of these is a perfect square? (a) 529 (b) 531 (c) 572
  3. 3.What is the smallest whole number by which 147 must be multiplied to get a perfect square?
  4. 4.What is the sum of the first 10 odd numbers (1 + 3 + 5 + …)?
  5. 5.A square garden has an area of 2809 square m. How long is each side (in m)?
  6. 6.What is the sum of the first 11 odd numbers (1 + 3 + 5 + …)?
  7. 7.A square garden has an area of 100 square m. How long is each side (in m)?
  8. 8.A square garden has an area of 121 square m. How long is each side (in m)?
  9. 9.What is 24²? =
  10. 10.What is 47²? =
  11. 11.What is the smallest whole number by which 240 must be divided to get a perfect square?
  12. 12.What is the sum of the first 14 odd numbers (1 + 3 + 5 + …)?
  13. 13.What is 43²? =
  14. 14.What is √841? =
  15. 15.What is the sum of the first 30 odd numbers (1 + 3 + 5 + …)?
  16. 16.How many whole numbers lie between 14² and 15²?
  17. 17.How many whole numbers lie between 38² and 39²?
  18. 18.What is 22²? =
  19. 19.What is 42²? =
  20. 20.What is 72²? =
  21. 21.What is the sum of the first 22 odd numbers (1 + 3 + 5 + …)?
  22. 22.What is 25²? =
  23. 23.Which of these is a perfect square? (a) 709 (b) 676 (c) 684
  24. 24.What is the smallest whole number by which 48 must be multiplied to get a perfect square?
  25. 25.A square garden has an area of 144 square m. How long is each side (in m)?
  26. 26.A square garden has an area of 36 square m. How long is each side (in m)?
  27. 27.How many whole numbers lie between 47² and 48²?
  28. 28.A square garden has an area of 1225 square m. How long is each side (in m)?
  29. 29.How many whole numbers lie between 39² and 40²?
  30. 30.What is √1225? =
  31. 31.Which of these is a perfect square? (a) 668 (b) 625 (c) 642
  32. 32.What is √5476? =
  33. 33.What is the smallest whole number by which 375 must be divided to get a perfect square?
  34. 34.What is 86²? =
  35. 35.What is √256? =
  36. 36.A square garden has an area of 2601 square m. How long is each side (in m)?
  37. 37.Which of these is a perfect square? (a) 225 (b) 239 (c) 242
  38. 38.Which of these is a perfect square? (a) 109 (b) 101 (c) 100
  39. 39.A square garden has an area of 1764 square m. How long is each side (in m)?
  40. 40.What is 73²? =

Answer key

  1. 289
  2. 529
  3. 3
  4. 100
  5. 53
  6. 121
  7. 10
  8. 11
  9. 576
  10. 2209
  11. 15
  12. 196
  13. 1849
  14. 29
  15. 900
  16. 28
  17. 76
  18. 484
  19. 1764
  20. 5184
  21. 484
  22. 625
  23. 676
  24. 3
  25. 12
  26. 6
  27. 94
  28. 35
  29. 78
  30. 35
  31. 625
  32. 74
  33. 15
  34. 7396
  35. 16
  36. 51
  37. 225
  38. 100
  39. 42
  40. 5329

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