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Class 8 Maths Worksheet: Squares and Square Roots

Maths worksheets lesson 58: Squares and square roots · Set 108 · 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 20² and 21²?
  2. 2.How many whole numbers lie between 18² and 19²?
  3. 3.A square garden has an area of 1681 square m. How long is each side (in m)?
  4. 4.What is 78²? =
  5. 5.How many whole numbers lie between 17² and 18²?
  6. 6.A square garden has an area of 1369 square m. How long is each side (in m)?
  7. 7.What is 23²? =
  8. 8.How many whole numbers lie between 44² and 45²?
  9. 9.What is 68²? =
  10. 10.How many whole numbers lie between 8² and 9²?
  11. 11.What is 76²? =
  12. 12.How many whole numbers lie between 25² and 26²?
  13. 13.What is 48²? =
  14. 14.What is 96²? =
  15. 15.How many whole numbers lie between 11² and 12²?
  16. 16.Which of these is a perfect square? (a) 144 (b) 148 (c) 164
  17. 17.What is the smallest whole number by which 192 must be divided to get a perfect square?
  18. 18.Which of these is a perfect square? (a) 228 (b) 245 (c) 225
  19. 19.What is √5929? =
  20. 20.How many whole numbers lie between 34² and 35²?
  21. 21.What is 88²? =
  22. 22.What is √4900? =
  23. 23.What is 33²? =
  24. 24.Which of these is a perfect square? (a) 289 (b) 293 (c) 319
  25. 25.What is the sum of the first 7 odd numbers (1 + 3 + 5 + …)?
  26. 26.Which of these is a perfect square? (a) 1156 (b) 1162 (c) 1180
  27. 27.What is 83²? =
  28. 28.What is √4096? =
  29. 29.How many whole numbers lie between 7² and 8²?
  30. 30.What is √729? =
  31. 31.What is 90²? =
  32. 32.What is the smallest whole number by which 117 must be multiplied to get a perfect square?
  33. 33.Which of these is a perfect square? (a) 263 (b) 256 (c) 286
  34. 34.How many whole numbers lie between 9² and 10²?
  35. 35.A square garden has an area of 3481 square m. How long is each side (in m)?
  36. 36.What is √9604? =
  37. 37.Which of these is a perfect square? (a) 1467 (b) 1460 (c) 1444
  38. 38.How many whole numbers lie between 27² and 28²?
  39. 39.A square garden has an area of 3249 square m. How long is each side (in m)?
  40. 40.What is 86²? =

Answer key

  1. 40
  2. 36
  3. 41
  4. 6084
  5. 34
  6. 37
  7. 529
  8. 88
  9. 4624
  10. 16
  11. 5776
  12. 50
  13. 2304
  14. 9216
  15. 22
  16. 144
  17. 3
  18. 225
  19. 77
  20. 68
  21. 7744
  22. 70
  23. 1089
  24. 289
  25. 49
  26. 1156
  27. 6889
  28. 64
  29. 14
  30. 27
  31. 8100
  32. 13
  33. 256
  34. 18
  35. 59
  36. 98
  37. 1444
  38. 54
  39. 57
  40. 7396

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