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Class 8 Maths Worksheet: Squares and Square Roots

Maths worksheets lesson 58: Squares and square roots · Set 46 · 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 √625? =
  2. 2.What is the sum of the first 26 odd numbers (1 + 3 + 5 + …)?
  3. 3.What is 95²? =
  4. 4.A square garden has an area of 1156 square m. How long is each side (in m)?
  5. 5.How many whole numbers lie between 10² and 11²?
  6. 6.What is the sum of the first 6 odd numbers (1 + 3 + 5 + …)?
  7. 7.What is √1156? =
  8. 8.What is 25²? =
  9. 9.What is the smallest whole number by which 50 must be multiplied to get a perfect square?
  10. 10.What is the smallest whole number by which 20 must be divided to get a perfect square?
  11. 11.Which of these is a perfect square? (a) 238 (b) 229 (c) 225
  12. 12.Which of these is a perfect square? (a) 784 (b) 797 (c) 788
  13. 13.Which of these is a perfect square? (a) 295 (b) 291 (c) 289
  14. 14.A square garden has an area of 1936 square m. How long is each side (in m)?
  15. 15.What is 22²? =
  16. 16.A square garden has an area of 484 square m. How long is each side (in m)?
  17. 17.How many whole numbers lie between 18² and 19²?
  18. 18.How many whole numbers lie between 38² and 39²?
  19. 19.What is 73²? =
  20. 20.A square garden has an area of 2704 square m. How long is each side (in m)?
  21. 21.Which of these is a perfect square? (a) 394 (b) 386 (c) 361
  22. 22.What is √3969? =
  23. 23.What is √7921? =
  24. 24.What is √6561? =
  25. 25.What is 79²? =
  26. 26.What is 34²? =
  27. 27.Which of these is a perfect square? (a) 1024 (b) 1064 (c) 1058
  28. 28.What is the sum of the first 28 odd numbers (1 + 3 + 5 + …)?
  29. 29.Which of these is a perfect square? (a) 1475 (b) 1490 (c) 1444
  30. 30.What is the smallest whole number by which 832 must be multiplied to get a perfect square?
  31. 31.What is the smallest whole number by which 96 must be divided to get a perfect square?
  32. 32.What is √1296? =
  33. 33.What is √361? =
  34. 34.What is √121? =
  35. 35.What is the sum of the first 15 odd numbers (1 + 3 + 5 + …)?
  36. 36.How many whole numbers lie between 12² and 13²?
  37. 37.A square garden has an area of 100 square m. How long is each side (in m)?
  38. 38.Which of these is a perfect square? (a) 331 (b) 355 (c) 324
  39. 39.What is 80²? =
  40. 40.What is 28²? =

Answer key

  1. 25
  2. 676
  3. 9025
  4. 34
  5. 20
  6. 36
  7. 34
  8. 625
  9. 2
  10. 5
  11. 225
  12. 784
  13. 289
  14. 44
  15. 484
  16. 22
  17. 36
  18. 76
  19. 5329
  20. 52
  21. 361
  22. 63
  23. 89
  24. 81
  25. 6241
  26. 1156
  27. 1024
  28. 784
  29. 1444
  30. 13
  31. 6
  32. 36
  33. 19
  34. 11
  35. 225
  36. 24
  37. 10
  38. 324
  39. 6400
  40. 784

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