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Class 8 Maths Worksheet: Squares and Square Roots

Maths worksheets lesson 58: Squares and square roots · Set 400 · 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 √2304? =
  2. 2.What is the sum of the first 15 odd numbers (1 + 3 + 5 + …)?
  3. 3.What is √9025? =
  4. 4.What is 48²? =
  5. 5.Which of these is a perfect square? (a) 686 (b) 684 (c) 676
  6. 6.What is 94²? =
  7. 7.A square garden has an area of 784 square m. How long is each side (in m)?
  8. 8.How many whole numbers lie between 37² and 38²?
  9. 9.What is the sum of the first 26 odd numbers (1 + 3 + 5 + …)?
  10. 10.What is 33²? =
  11. 11.How many whole numbers lie between 10² and 11²?
  12. 12.What is 50²? =
  13. 13.What is the smallest whole number by which 44 must be multiplied to get a perfect square?
  14. 14.What is the sum of the first 27 odd numbers (1 + 3 + 5 + …)?
  15. 15.Which of these is a perfect square? (a) 1654 (b) 1631 (c) 1600
  16. 16.How many whole numbers lie between 39² and 40²?
  17. 17.What is √7921? =
  18. 18.What is the smallest whole number by which 275 must be multiplied to get a perfect square?
  19. 19.How many whole numbers lie between 15² and 16²?
  20. 20.Which of these is a perfect square? (a) 1444 (b) 1457 (c) 1481
  21. 21.What is 32²? =
  22. 22.What is 61²? =
  23. 23.What is the smallest whole number by which 405 must be multiplied to get a perfect square?
  24. 24.What is √6084? =
  25. 25.Which of these is a perfect square? (a) 536 (b) 567 (c) 529
  26. 26.What is 73²? =
  27. 27.What is the sum of the first 5 odd numbers (1 + 3 + 5 + …)?
  28. 28.What is the smallest whole number by which 208 must be multiplied to get a perfect square?
  29. 29.What is the smallest whole number by which 52 must be divided to get a perfect square?
  30. 30.What is 17²? =
  31. 31.What is the smallest whole number by which 108 must be divided to get a perfect square?
  32. 32.How many whole numbers lie between 30² and 31²?
  33. 33.A square garden has an area of 64 square m. How long is each side (in m)?
  34. 34.How many whole numbers lie between 13² and 14²?
  35. 35.How many whole numbers lie between 12² and 13²?
  36. 36.What is √3249? =
  37. 37.What is √1600? =
  38. 38.Which of these is a perfect square? (a) 1584 (b) 1596 (c) 1521
  39. 39.What is the sum of the first 28 odd numbers (1 + 3 + 5 + …)?
  40. 40.What is the smallest whole number by which 96 must be divided to get a perfect square?

Answer key

  1. 48
  2. 225
  3. 95
  4. 2304
  5. 676
  6. 8836
  7. 28
  8. 74
  9. 676
  10. 1089
  11. 20
  12. 2500
  13. 11
  14. 729
  15. 1600
  16. 78
  17. 89
  18. 11
  19. 30
  20. 1444
  21. 1024
  22. 3721
  23. 5
  24. 78
  25. 529
  26. 5329
  27. 25
  28. 13
  29. 13
  30. 289
  31. 3
  32. 60
  33. 8
  34. 26
  35. 24
  36. 57
  37. 40
  38. 1521
  39. 784
  40. 6

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