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Class 8 Maths Worksheet: Squares and Square Roots

Maths worksheets lesson 58: Squares and square roots · Set 120 · 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.A square garden has an area of 3364 square m. How long is each side (in m)?
  2. 2.What is 89²? =
  3. 3.Which of these is a perfect square? (a) 177 (b) 192 (c) 169
  4. 4.What is 39²? =
  5. 5.What is √9801? =
  6. 6.What is 22²? =
  7. 7.Which of these is a perfect square? (a) 1156 (b) 1171 (c) 1195
  8. 8.What is 62²? =
  9. 9.What is the sum of the first 18 odd numbers (1 + 3 + 5 + …)?
  10. 10.What is √1600? =
  11. 11.How many whole numbers lie between 11² and 12²?
  12. 12.What is 54²? =
  13. 13.What is the sum of the first 13 odd numbers (1 + 3 + 5 + …)?
  14. 14.What is the sum of the first 12 odd numbers (1 + 3 + 5 + …)?
  15. 15.What is the smallest whole number by which 250 must be multiplied to get a perfect square?
  16. 16.What is √5776? =
  17. 17.What is the smallest whole number by which 98 must be multiplied to get a perfect square?
  18. 18.What is √3364? =
  19. 19.How many whole numbers lie between 17² and 18²?
  20. 20.What is 85²? =
  21. 21.What is 48²? =
  22. 22.What is 57²? =
  23. 23.What is the smallest whole number by which 360 must be divided to get a perfect square?
  24. 24.What is the smallest whole number by which 8 must be multiplied to get a perfect square?
  25. 25.Which of these is a perfect square? (a) 644 (b) 625 (c) 670
  26. 26.What is √3969? =
  27. 27.How many whole numbers lie between 26² and 27²?
  28. 28.What is 47²? =
  29. 29.What is 66²? =
  30. 30.What is √625? =
  31. 31.What is √5041? =
  32. 32.What is 84²? =
  33. 33.What is √2209? =
  34. 34.What is 83²? =
  35. 35.What is 87²? =
  36. 36.Which of these is a perfect square? (a) 410 (b) 418 (c) 400
  37. 37.What is the smallest whole number by which 150 must be divided to get a perfect square?
  38. 38.What is 41²? =
  39. 39.A square garden has an area of 2809 square m. How long is each side (in m)?
  40. 40.What is 33²? =

Answer key

  1. 58
  2. 7921
  3. 169
  4. 1521
  5. 99
  6. 484
  7. 1156
  8. 3844
  9. 324
  10. 40
  11. 22
  12. 2916
  13. 169
  14. 144
  15. 10
  16. 76
  17. 2
  18. 58
  19. 34
  20. 7225
  21. 2304
  22. 3249
  23. 10
  24. 2
  25. 625
  26. 63
  27. 52
  28. 2209
  29. 4356
  30. 25
  31. 71
  32. 7056
  33. 47
  34. 6889
  35. 7569
  36. 400
  37. 6
  38. 1681
  39. 53
  40. 1089

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