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Class 8 Maths Worksheet: Squares and Square Roots

Maths worksheets lesson 58: Squares and square roots · Set 636 · 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 the smallest whole number by which 52 must be multiplied to get a perfect square?
  2. 2.What is the smallest whole number by which 27 must be multiplied to get a perfect square?
  3. 3.What is 44²? =
  4. 4.A square garden has an area of 289 square m. How long is each side (in m)?
  5. 5.What is √1681? =
  6. 6.How many whole numbers lie between 21² and 22²?
  7. 7.Which of these is a perfect square? (a) 1331 (b) 1361 (c) 1296
  8. 8.What is the sum of the first 12 odd numbers (1 + 3 + 5 + …)?
  9. 9.What is the smallest whole number by which 45 must be multiplied to get a perfect square?
  10. 10.What is 64²? =
  11. 11.What is 50²? =
  12. 12.What is the sum of the first 14 odd numbers (1 + 3 + 5 + …)?
  13. 13.What is √5776? =
  14. 14.How many whole numbers lie between 43² and 44²?
  15. 15.What is 51²? =
  16. 16.What is the sum of the first 8 odd numbers (1 + 3 + 5 + …)?
  17. 17.How many whole numbers lie between 15² and 16²?
  18. 18.What is √2916? =
  19. 19.What is the smallest whole number by which 60 must be divided to get a perfect square?
  20. 20.What is the sum of the first 15 odd numbers (1 + 3 + 5 + …)?
  21. 21.How many whole numbers lie between 35² and 36²?
  22. 22.What is the smallest whole number by which 80 must be divided to get a perfect square?
  23. 23.What is the sum of the first 9 odd numbers (1 + 3 + 5 + …)?
  24. 24.Which of these is a perfect square? (a) 676 (b) 688 (c) 726
  25. 25.What is √900? =
  26. 26.What is the smallest whole number by which 360 must be multiplied to get a perfect square?
  27. 27.Which of these is a perfect square? (a) 1225 (b) 1291 (c) 1260
  28. 28.A square garden has an area of 100 square m. How long is each side (in m)?
  29. 29.What is 65²? =
  30. 30.Which of these is a perfect square? (a) 357 (b) 324 (c) 352
  31. 31.What is the sum of the first 7 odd numbers (1 + 3 + 5 + …)?
  32. 32.What is √5041? =
  33. 33.A square garden has an area of 400 square m. How long is each side (in m)?
  34. 34.What is √729? =
  35. 35.What is 27²? =
  36. 36.How many whole numbers lie between 20² and 21²?
  37. 37.What is 69²? =
  38. 38.Which of these is a perfect square? (a) 105 (b) 100 (c) 110
  39. 39.Which of these is a perfect square? (a) 258 (b) 273 (c) 256
  40. 40.A square garden has an area of 49 square m. How long is each side (in m)?

Answer key

  1. 13
  2. 3
  3. 1936
  4. 17
  5. 41
  6. 42
  7. 1296
  8. 144
  9. 5
  10. 4096
  11. 2500
  12. 196
  13. 76
  14. 86
  15. 2601
  16. 64
  17. 30
  18. 54
  19. 15
  20. 225
  21. 70
  22. 5
  23. 81
  24. 676
  25. 30
  26. 10
  27. 1225
  28. 10
  29. 4225
  30. 324
  31. 49
  32. 71
  33. 20
  34. 27
  35. 729
  36. 40
  37. 4761
  38. 100
  39. 256
  40. 7

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