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Class 8 Maths Worksheet: Squares and Square Roots

Maths worksheets lesson 58: Squares and square roots · Set 92 · 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.How many whole numbers lie between 47² and 48²?
  2. 2.What is √2809? =
  3. 3.Which of these is a perfect square? (a) 132 (b) 129 (c) 121
  4. 4.What is 32²? =
  5. 5.A square garden has an area of 1849 square m. How long is each side (in m)?
  6. 6.Which of these is a perfect square? (a) 325 (b) 324 (c) 357
  7. 7.What is √1296? =
  8. 8.A square garden has an area of 1681 square m. How long is each side (in m)?
  9. 9.What is the sum of the first 17 odd numbers (1 + 3 + 5 + …)?
  10. 10.What is the smallest whole number by which 504 must be multiplied to get a perfect square?
  11. 11.What is 66²? =
  12. 12.What is 70²? =
  13. 13.What is √5776? =
  14. 14.What is 22²? =
  15. 15.What is √9801? =
  16. 16.How many whole numbers lie between 49² and 50²?
  17. 17.Which of these is a perfect square? (a) 1598 (b) 1521 (c) 1589
  18. 18.Which of these is a perfect square? (a) 841 (b) 853 (c) 874
  19. 19.What is the smallest whole number by which 98 must be multiplied to get a perfect square?
  20. 20.What is √3969? =
  21. 21.What is the smallest whole number by which 28 must be divided to get a perfect square?
  22. 22.What is √3481? =
  23. 23.What is 31²? =
  24. 24.A square garden has an area of 169 square m. How long is each side (in m)?
  25. 25.What is the sum of the first 28 odd numbers (1 + 3 + 5 + …)?
  26. 26.What is √4356? =
  27. 27.How many whole numbers lie between 7² and 8²?
  28. 28.What is the smallest whole number by which 147 must be multiplied to get a perfect square?
  29. 29.What is √484? =
  30. 30.A square garden has an area of 961 square m. How long is each side (in m)?
  31. 31.What is the sum of the first 27 odd numbers (1 + 3 + 5 + …)?
  32. 32.What is the sum of the first 24 odd numbers (1 + 3 + 5 + …)?
  33. 33.What is √9604? =
  34. 34.What is the smallest whole number by which 396 must be multiplied to get a perfect square?
  35. 35.How many whole numbers lie between 6² and 7²?
  36. 36.What is the sum of the first 16 odd numbers (1 + 3 + 5 + …)?
  37. 37.Which of these is a perfect square? (a) 400 (b) 422 (c) 411
  38. 38.What is the smallest whole number by which 98 must be divided to get a perfect square?
  39. 39.Which of these is a perfect square? (a) 255 (b) 241 (c) 225
  40. 40.What is the smallest whole number by which 250 must be divided to get a perfect square?

Answer key

  1. 94
  2. 53
  3. 121
  4. 1024
  5. 43
  6. 324
  7. 36
  8. 41
  9. 289
  10. 14
  11. 4356
  12. 4900
  13. 76
  14. 484
  15. 99
  16. 98
  17. 1521
  18. 841
  19. 2
  20. 63
  21. 7
  22. 59
  23. 961
  24. 13
  25. 784
  26. 66
  27. 14
  28. 3
  29. 22
  30. 31
  31. 729
  32. 576
  33. 98
  34. 11
  35. 12
  36. 256
  37. 400
  38. 2
  39. 225
  40. 10

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