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Class 8 Maths Worksheet: Squares and Square Roots

Maths worksheets lesson 58: Squares and square roots · Set 426 · 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 96²? =
  2. 2.What is √8464? =
  3. 3.What is the sum of the first 25 odd numbers (1 + 3 + 5 + …)?
  4. 4.Which of these is a perfect square? (a) 1555 (b) 1521 (c) 1551
  5. 5.What is the smallest whole number by which 175 must be multiplied to get a perfect square?
  6. 6.What is 38²? =
  7. 7.Which of these is a perfect square? (a) 1225 (b) 1237 (c) 1269
  8. 8.What is the sum of the first 12 odd numbers (1 + 3 + 5 + …)?
  9. 9.What is the smallest whole number by which 1134 must be multiplied to get a perfect square?
  10. 10.What is 20²? =
  11. 11.What is 66²? =
  12. 12.What is 12²? =
  13. 13.What is √900? =
  14. 14.What is 61²? =
  15. 15.How many whole numbers lie between 44² and 45²?
  16. 16.Which of these is a perfect square? (a) 1444 (b) 1500 (c) 1506
  17. 17.What is the smallest whole number by which 275 must be divided to get a perfect square?
  18. 18.How many whole numbers lie between 42² and 43²?
  19. 19.A square garden has an area of 2601 square m. How long is each side (in m)?
  20. 20.How many whole numbers lie between 20² and 21²?
  21. 21.What is 32²? =
  22. 22.What is the smallest whole number by which 150 must be multiplied to get a perfect square?
  23. 23.A square garden has an area of 2209 square m. How long is each side (in m)?
  24. 24.What is the sum of the first 6 odd numbers (1 + 3 + 5 + …)?
  25. 25.Which of these is a perfect square? (a) 363 (b) 388 (c) 361
  26. 26.What is 29²? =
  27. 27.A square garden has an area of 49 square m. How long is each side (in m)?
  28. 28.How many whole numbers lie between 18² and 19²?
  29. 29.Which of these is a perfect square? (a) 174 (b) 176 (c) 169
  30. 30.How many whole numbers lie between 5² and 6²?
  31. 31.What is 89²? =
  32. 32.How many whole numbers lie between 6² and 7²?
  33. 33.What is the sum of the first 28 odd numbers (1 + 3 + 5 + …)?
  34. 34.What is 26²? =
  35. 35.What is √484? =
  36. 36.What is √225? =
  37. 37.What is 33²? =
  38. 38.What is 85²? =
  39. 39.What is 37²? =
  40. 40.What is the smallest whole number by which 75 must be divided to get a perfect square?

Answer key

  1. 9216
  2. 92
  3. 625
  4. 1521
  5. 7
  6. 1444
  7. 1225
  8. 144
  9. 14
  10. 400
  11. 4356
  12. 144
  13. 30
  14. 3721
  15. 88
  16. 1444
  17. 11
  18. 84
  19. 51
  20. 40
  21. 1024
  22. 6
  23. 47
  24. 36
  25. 361
  26. 841
  27. 7
  28. 36
  29. 169
  30. 10
  31. 7921
  32. 12
  33. 784
  34. 676
  35. 22
  36. 15
  37. 1089
  38. 7225
  39. 1369
  40. 3

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