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Class 8 Maths Worksheet: Squares and Square Roots

Maths worksheets lesson 58: Squares and square roots · Set 676 · 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 √6724? =
  2. 2.A square garden has an area of 2209 square m. How long is each side (in m)?
  3. 3.Which of these is a perfect square? (a) 1623 (b) 1625 (c) 1600
  4. 4.Which of these is a perfect square? (a) 389 (b) 366 (c) 361
  5. 5.What is √2704? =
  6. 6.How many whole numbers lie between 40² and 41²?
  7. 7.What is √9409? =
  8. 8.What is √4624? =
  9. 9.What is √7569? =
  10. 10.What is √3136? =
  11. 11.What is the sum of the first 20 odd numbers (1 + 3 + 5 + …)?
  12. 12.What is 37²? =
  13. 13.What is 31²? =
  14. 14.How many whole numbers lie between 49² and 50²?
  15. 15.What is 50²? =
  16. 16.What is 51²? =
  17. 17.Which of these is a perfect square? (a) 213 (b) 196 (c) 223
  18. 18.What is √900? =
  19. 19.What is √2500? =
  20. 20.What is 74²? =
  21. 21.Which of these is a perfect square? (a) 430 (b) 404 (c) 400
  22. 22.What is 49²? =
  23. 23.What is the sum of the first 8 odd numbers (1 + 3 + 5 + …)?
  24. 24.What is √8836? =
  25. 25.What is 43²? =
  26. 26.What is the smallest whole number by which 1215 must be divided to get a perfect square?
  27. 27.A square garden has an area of 64 square m. How long is each side (in m)?
  28. 28.What is 42²? =
  29. 29.A square garden has an area of 784 square m. How long is each side (in m)?
  30. 30.What is the sum of the first 10 odd numbers (1 + 3 + 5 + …)?
  31. 31.What is the smallest whole number by which 12 must be multiplied to get a perfect square?
  32. 32.What is 63²? =
  33. 33.A square garden has an area of 121 square m. How long is each side (in m)?
  34. 34.What is the sum of the first 30 odd numbers (1 + 3 + 5 + …)?
  35. 35.What is √9216? =
  36. 36.What is the sum of the first 7 odd numbers (1 + 3 + 5 + …)?
  37. 37.What is the smallest whole number by which 54 must be multiplied to get a perfect square?
  38. 38.What is the sum of the first 14 odd numbers (1 + 3 + 5 + …)?
  39. 39.What is the smallest whole number by which 891 must be multiplied to get a perfect square?
  40. 40.What is 40²? =

Answer key

  1. 82
  2. 47
  3. 1600
  4. 361
  5. 52
  6. 80
  7. 97
  8. 68
  9. 87
  10. 56
  11. 400
  12. 1369
  13. 961
  14. 98
  15. 2500
  16. 2601
  17. 196
  18. 30
  19. 50
  20. 5476
  21. 400
  22. 2401
  23. 64
  24. 94
  25. 1849
  26. 15
  27. 8
  28. 1764
  29. 28
  30. 100
  31. 3
  32. 3969
  33. 11
  34. 900
  35. 96
  36. 49
  37. 6
  38. 196
  39. 11
  40. 1600

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