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Class 8 Maths Worksheet: Squares and Square Roots

Maths worksheets lesson 58: Squares and square roots · Set 552 · 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 23² and 24²?
  2. 2.Which of these is a perfect square? (a) 620 (b) 581 (c) 576
  3. 3.What is √1849? =
  4. 4.How many whole numbers lie between 10² and 11²?
  5. 5.Which of these is a perfect square? (a) 147 (b) 150 (c) 144
  6. 6.What is the sum of the first 18 odd numbers (1 + 3 + 5 + …)?
  7. 7.Which of these is a perfect square? (a) 500 (b) 484 (c) 522
  8. 8.Which of these is a perfect square? (a) 236 (b) 225 (c) 247
  9. 9.Which of these is a perfect square? (a) 1013 (b) 961 (c) 966
  10. 10.A square garden has an area of 144 square m. How long is each side (in m)?
  11. 11.What is √961? =
  12. 12.What is the sum of the first 7 odd numbers (1 + 3 + 5 + …)?
  13. 13.Which of these is a perfect square? (a) 296 (b) 289 (c) 323
  14. 14.What is the smallest whole number by which 18 must be divided to get a perfect square?
  15. 15.What is 35²? =
  16. 16.A square garden has an area of 841 square m. How long is each side (in m)?
  17. 17.How many whole numbers lie between 40² and 41²?
  18. 18.What is 82²? =
  19. 19.What is √7056? =
  20. 20.What is the smallest whole number by which 150 must be multiplied to get a perfect square?
  21. 21.How many whole numbers lie between 41² and 42²?
  22. 22.What is the smallest whole number by which 63 must be divided to get a perfect square?
  23. 23.What is 73²? =
  24. 24.What is the sum of the first 22 odd numbers (1 + 3 + 5 + …)?
  25. 25.How many whole numbers lie between 49² and 50²?
  26. 26.Which of these is a perfect square? (a) 453 (b) 441 (c) 481
  27. 27.What is the smallest whole number by which 52 must be divided to get a perfect square?
  28. 28.A square garden has an area of 729 square m. How long is each side (in m)?
  29. 29.Which of these is a perfect square? (a) 390 (b) 399 (c) 361
  30. 30.How many whole numbers lie between 16² and 17²?
  31. 31.What is 51²? =
  32. 32.What is the smallest whole number by which 504 must be multiplied to get a perfect square?
  33. 33.How many whole numbers lie between 9² and 10²?
  34. 34.What is 52²? =
  35. 35.How many whole numbers lie between 35² and 36²?
  36. 36.What is the smallest whole number by which 48 must be multiplied to get a perfect square?
  37. 37.What is the sum of the first 27 odd numbers (1 + 3 + 5 + …)?
  38. 38.What is √7569? =
  39. 39.What is √625? =
  40. 40.What is 12²? =

Answer key

  1. 46
  2. 576
  3. 43
  4. 20
  5. 144
  6. 324
  7. 484
  8. 225
  9. 961
  10. 12
  11. 31
  12. 49
  13. 289
  14. 2
  15. 1225
  16. 29
  17. 80
  18. 6724
  19. 84
  20. 6
  21. 82
  22. 7
  23. 5329
  24. 484
  25. 98
  26. 441
  27. 13
  28. 27
  29. 361
  30. 32
  31. 2601
  32. 14
  33. 18
  34. 2704
  35. 70
  36. 3
  37. 729
  38. 87
  39. 25
  40. 144

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