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Class 8 Maths Worksheet: Squares and Square Roots

Maths worksheets lesson 58: Squares and square roots · Set 31 · 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 √529? =
  2. 2.Which of these is a perfect square? (a) 1225 (b) 1276 (c) 1251
  3. 3.What is the smallest whole number by which 396 must be divided to get a perfect square?
  4. 4.Which of these is a perfect square? (a) 253 (b) 243 (c) 225
  5. 5.What is √225? =
  6. 6.A square garden has an area of 361 square m. How long is each side (in m)?
  7. 7.What is √121? =
  8. 8.What is the smallest whole number by which 250 must be divided to get a perfect square?
  9. 9.What is the sum of the first 15 odd numbers (1 + 3 + 5 + …)?
  10. 10.How many whole numbers lie between 11² and 12²?
  11. 11.What is 98²? =
  12. 12.How many whole numbers lie between 43² and 44²?
  13. 13.What is 36²? =
  14. 14.How many whole numbers lie between 27² and 28²?
  15. 15.What is the sum of the first 18 odd numbers (1 + 3 + 5 + …)?
  16. 16.A square garden has an area of 1225 square m. How long is each side (in m)?
  17. 17.How many whole numbers lie between 23² and 24²?
  18. 18.A square garden has an area of 2116 square m. How long is each side (in m)?
  19. 19.What is √5929? =
  20. 20.What is the smallest whole number by which 896 must be divided to get a perfect square?
  21. 21.What is the smallest whole number by which 18 must be multiplied to get a perfect square?
  22. 22.What is 62²? =
  23. 23.Which of these is a perfect square? (a) 149 (b) 150 (c) 144
  24. 24.What is the smallest whole number by which 1053 must be divided to get a perfect square?
  25. 25.What is 91²? =
  26. 26.Which of these is a perfect square? (a) 529 (b) 571 (c) 543
  27. 27.What is the sum of the first 25 odd numbers (1 + 3 + 5 + …)?
  28. 28.What is 43²? =
  29. 29.A square garden has an area of 225 square m. How long is each side (in m)?
  30. 30.What is √5625? =
  31. 31.What is √5041? =
  32. 32.What is 65²? =
  33. 33.How many whole numbers lie between 45² and 46²?
  34. 34.What is the sum of the first 21 odd numbers (1 + 3 + 5 + …)?
  35. 35.What is √4225? =
  36. 36.What is the smallest whole number by which 48 must be multiplied to get a perfect square?
  37. 37.How many whole numbers lie between 38² and 39²?
  38. 38.How many whole numbers lie between 29² and 30²?
  39. 39.What is the sum of the first 14 odd numbers (1 + 3 + 5 + …)?
  40. 40.What is 66²? =

Answer key

  1. 23
  2. 1225
  3. 11
  4. 225
  5. 15
  6. 19
  7. 11
  8. 10
  9. 225
  10. 22
  11. 9604
  12. 86
  13. 1296
  14. 54
  15. 324
  16. 35
  17. 46
  18. 46
  19. 77
  20. 14
  21. 2
  22. 3844
  23. 144
  24. 13
  25. 8281
  26. 529
  27. 625
  28. 1849
  29. 15
  30. 75
  31. 71
  32. 4225
  33. 90
  34. 441
  35. 65
  36. 3
  37. 76
  38. 58
  39. 196
  40. 4356

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