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Class 8 Maths Worksheet: Squares and Square Roots

Maths worksheets lesson 58: Squares and square roots · Set 634 · 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 162 must be multiplied to get a perfect square?
  2. 2.A square garden has an area of 169 square m. How long is each side (in m)?
  3. 3.How many whole numbers lie between 15² and 16²?
  4. 4.What is √1521? =
  5. 5.How many whole numbers lie between 27² and 28²?
  6. 6.What is the smallest whole number by which 40 must be multiplied to get a perfect square?
  7. 7.What is 46²? =
  8. 8.How many whole numbers lie between 34² and 35²?
  9. 9.Which of these is a perfect square? (a) 366 (b) 361 (c) 376
  10. 10.Which of these is a perfect square? (a) 1178 (b) 1157 (c) 1156
  11. 11.What is √3249? =
  12. 12.What is √784? =
  13. 13.What is 23²? =
  14. 14.A square garden has an area of 729 square m. How long is each side (in m)?
  15. 15.How many whole numbers lie between 33² and 34²?
  16. 16.A square garden has an area of 841 square m. How long is each side (in m)?
  17. 17.Which of these is a perfect square? (a) 170 (b) 169 (c) 181
  18. 18.What is the sum of the first 16 odd numbers (1 + 3 + 5 + …)?
  19. 19.What is the smallest whole number by which 540 must be multiplied to get a perfect square?
  20. 20.Which of these is a perfect square? (a) 685 (b) 676 (c) 710
  21. 21.What is √441? =
  22. 22.What is the sum of the first 27 odd numbers (1 + 3 + 5 + …)?
  23. 23.What is the sum of the first 25 odd numbers (1 + 3 + 5 + …)?
  24. 24.Which of these is a perfect square? (a) 841 (b) 856 (c) 853
  25. 25.What is the sum of the first 30 odd numbers (1 + 3 + 5 + …)?
  26. 26.What is the sum of the first 13 odd numbers (1 + 3 + 5 + …)?
  27. 27.What is 40²? =
  28. 28.A square garden has an area of 49 square m. How long is each side (in m)?
  29. 29.What is 62²? =
  30. 30.What is 67²? =
  31. 31.Which of these is a perfect square? (a) 1331 (b) 1296 (c) 1316
  32. 32.What is the sum of the first 9 odd numbers (1 + 3 + 5 + …)?
  33. 33.What is the smallest whole number by which 539 must be divided to get a perfect square?
  34. 34.What is 16²? =
  35. 35.What is 18²? =
  36. 36.What is the smallest whole number by which 96 must be divided to get a perfect square?
  37. 37.What is 49²? =
  38. 38.A square garden has an area of 1600 square m. How long is each side (in m)?
  39. 39.How many whole numbers lie between 6² and 7²?
  40. 40.What is 75²? =

Answer key

  1. 2
  2. 13
  3. 30
  4. 39
  5. 54
  6. 10
  7. 2116
  8. 68
  9. 361
  10. 1156
  11. 57
  12. 28
  13. 529
  14. 27
  15. 66
  16. 29
  17. 169
  18. 256
  19. 15
  20. 676
  21. 21
  22. 729
  23. 625
  24. 841
  25. 900
  26. 169
  27. 1600
  28. 7
  29. 3844
  30. 4489
  31. 1296
  32. 81
  33. 11
  34. 256
  35. 324
  36. 6
  37. 2401
  38. 40
  39. 12
  40. 5625

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