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Class 8 Maths Worksheet: Squares and Square Roots

Maths worksheets lesson 58: Squares and square roots · Set 24 · 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 √256? =
  2. 2.A square garden has an area of 784 square m. How long is each side (in m)?
  3. 3.What is 89²? =
  4. 4.What is the smallest whole number by which 162 must be divided to get a perfect square?
  5. 5.What is the smallest whole number by which 490 must be multiplied to get a perfect square?
  6. 6.Which of these is a perfect square? (a) 704 (b) 676 (c) 715
  7. 7.What is the sum of the first 23 odd numbers (1 + 3 + 5 + …)?
  8. 8.A square garden has an area of 196 square m. How long is each side (in m)?
  9. 9.What is the sum of the first 17 odd numbers (1 + 3 + 5 + …)?
  10. 10.A square garden has an area of 1089 square m. How long is each side (in m)?
  11. 11.Which of these is a perfect square? (a) 624 (b) 594 (c) 576
  12. 12.What is √361? =
  13. 13.Which of these is a perfect square? (a) 362 (b) 381 (c) 361
  14. 14.What is the sum of the first 11 odd numbers (1 + 3 + 5 + …)?
  15. 15.What is √1156? =
  16. 16.What is √2116? =
  17. 17.What is √3025? =
  18. 18.How many whole numbers lie between 47² and 48²?
  19. 19.What is the sum of the first 26 odd numbers (1 + 3 + 5 + …)?
  20. 20.What is 15²? =
  21. 21.Which of these is a perfect square? (a) 1521 (b) 1548 (c) 1526
  22. 22.What is the sum of the first 13 odd numbers (1 + 3 + 5 + …)?
  23. 23.What is 33²? =
  24. 24.A square garden has an area of 225 square m. How long is each side (in m)?
  25. 25.Which of these is a perfect square? (a) 349 (b) 337 (c) 324
  26. 26.What is 52²? =
  27. 27.What is the smallest whole number by which 539 must be divided to get a perfect square?
  28. 28.What is the smallest whole number by which 52 must be multiplied to get a perfect square?
  29. 29.What is the sum of the first 24 odd numbers (1 + 3 + 5 + …)?
  30. 30.What is 46²? =
  31. 31.How many whole numbers lie between 10² and 11²?
  32. 32.How many whole numbers lie between 21² and 22²?
  33. 33.What is 35²? =
  34. 34.Which of these is a perfect square? (a) 1240 (b) 1287 (c) 1225
  35. 35.How many whole numbers lie between 49² and 50²?
  36. 36.A square garden has an area of 1764 square m. How long is each side (in m)?
  37. 37.Which of these is a perfect square? (a) 256 (b) 282 (c) 281
  38. 38.Which of these is a perfect square? (a) 841 (b) 890 (c) 876
  39. 39.What is √1681? =
  40. 40.What is the smallest whole number by which 28 must be divided to get a perfect square?

Answer key

  1. 16
  2. 28
  3. 7921
  4. 2
  5. 10
  6. 676
  7. 529
  8. 14
  9. 289
  10. 33
  11. 576
  12. 19
  13. 361
  14. 121
  15. 34
  16. 46
  17. 55
  18. 94
  19. 676
  20. 225
  21. 1521
  22. 169
  23. 1089
  24. 15
  25. 324
  26. 2704
  27. 11
  28. 13
  29. 576
  30. 2116
  31. 20
  32. 42
  33. 1225
  34. 1225
  35. 98
  36. 42
  37. 256
  38. 841
  39. 41
  40. 7

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