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Class 8 Maths Worksheet: Squares and Square Roots

Maths worksheets lesson 58: Squares and square roots · Set 119 · 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) 245 (b) 225 (c) 228
  2. 2.What is the sum of the first 5 odd numbers (1 + 3 + 5 + …)?
  3. 3.What is 31²? =
  4. 4.What is √8836? =
  5. 5.What is 84²? =
  6. 6.What is the smallest whole number by which 224 must be multiplied to get a perfect square?
  7. 7.What is the smallest whole number by which 63 must be multiplied to get a perfect square?
  8. 8.A square garden has an area of 1369 square m. How long is each side (in m)?
  9. 9.What is 70²? =
  10. 10.What is √961? =
  11. 11.What is √2916? =
  12. 12.What is √5184? =
  13. 13.A square garden has an area of 400 square m. How long is each side (in m)?
  14. 14.What is 83²? =
  15. 15.What is 26²? =
  16. 16.What is the sum of the first 13 odd numbers (1 + 3 + 5 + …)?
  17. 17.What is the smallest whole number by which 44 must be divided to get a perfect square?
  18. 18.What is √5776? =
  19. 19.What is 44²? =
  20. 20.What is the sum of the first 7 odd numbers (1 + 3 + 5 + …)?
  21. 21.Which of these is a perfect square? (a) 410 (b) 421 (c) 400
  22. 22.What is 72²? =
  23. 23.What is 36²? =
  24. 24.What is the smallest whole number by which 486 must be divided to get a perfect square?
  25. 25.A square garden has an area of 900 square m. How long is each side (in m)?
  26. 26.What is 94²? =
  27. 27.What is the smallest whole number by which 1134 must be multiplied to get a perfect square?
  28. 28.What is the sum of the first 8 odd numbers (1 + 3 + 5 + …)?
  29. 29.What is the smallest whole number by which 735 must be divided to get a perfect square?
  30. 30.What is 16²? =
  31. 31.What is √9801? =
  32. 32.What is the smallest whole number by which 52 must be divided to get a perfect square?
  33. 33.How many whole numbers lie between 20² and 21²?
  34. 34.What is the sum of the first 23 odd numbers (1 + 3 + 5 + …)?
  35. 35.What is √7396? =
  36. 36.A square garden has an area of 169 square m. How long is each side (in m)?
  37. 37.Which of these is a perfect square? (a) 364 (b) 386 (c) 361
  38. 38.How many whole numbers lie between 21² and 22²?
  39. 39.What is √8281? =
  40. 40.What is √3025? =

Answer key

  1. 225
  2. 25
  3. 961
  4. 94
  5. 7056
  6. 14
  7. 7
  8. 37
  9. 4900
  10. 31
  11. 54
  12. 72
  13. 20
  14. 6889
  15. 676
  16. 169
  17. 11
  18. 76
  19. 1936
  20. 49
  21. 400
  22. 5184
  23. 1296
  24. 6
  25. 30
  26. 8836
  27. 14
  28. 64
  29. 15
  30. 256
  31. 99
  32. 13
  33. 40
  34. 529
  35. 86
  36. 13
  37. 361
  38. 42
  39. 91
  40. 55

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