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Class 8 Maths Worksheet: Squares and Square Roots

Maths worksheets lesson 58: Squares and square roots · Set 384 · 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 48²? =
  2. 2.How many whole numbers lie between 8² and 9²?
  3. 3.What is 36²? =
  4. 4.How many whole numbers lie between 11² and 12²?
  5. 5.What is the smallest whole number by which 1134 must be divided to get a perfect square?
  6. 6.What is the sum of the first 30 odd numbers (1 + 3 + 5 + …)?
  7. 7.What is the sum of the first 7 odd numbers (1 + 3 + 5 + …)?
  8. 8.What is 18²? =
  9. 9.How many whole numbers lie between 6² and 7²?
  10. 10.What is √144? =
  11. 11.How many whole numbers lie between 28² and 29²?
  12. 12.What is the sum of the first 18 odd numbers (1 + 3 + 5 + …)?
  13. 13.What is √625? =
  14. 14.What is the sum of the first 15 odd numbers (1 + 3 + 5 + …)?
  15. 15.Which of these is a perfect square? (a) 1168 (b) 1156 (c) 1163
  16. 16.What is 56²? =
  17. 17.Which of these is a perfect square? (a) 1039 (b) 1024 (c) 1040
  18. 18.What is √2500? =
  19. 19.What is the smallest whole number by which 162 must be multiplied to get a perfect square?
  20. 20.What is the smallest whole number by which 360 must be multiplied to get a perfect square?
  21. 21.Which of these is a perfect square? (a) 1369 (b) 1425 (c) 1396
  22. 22.What is 33²? =
  23. 23.What is 85²? =
  24. 24.A square garden has an area of 3364 square m. How long is each side (in m)?
  25. 25.How many whole numbers lie between 42² and 43²?
  26. 26.What is the sum of the first 16 odd numbers (1 + 3 + 5 + …)?
  27. 27.What is 40²? =
  28. 28.What is the sum of the first 14 odd numbers (1 + 3 + 5 + …)?
  29. 29.How many whole numbers lie between 32² and 33²?
  30. 30.What is 16²? =
  31. 31.A square garden has an area of 3249 square m. How long is each side (in m)?
  32. 32.What is 60²? =
  33. 33.What is the sum of the first 22 odd numbers (1 + 3 + 5 + …)?
  34. 34.What is the smallest whole number by which 192 must be divided to get a perfect square?
  35. 35.What is the sum of the first 17 odd numbers (1 + 3 + 5 + …)?
  36. 36.A square garden has an area of 256 square m. How long is each side (in m)?
  37. 37.What is 82²? =
  38. 38.What is √6400? =
  39. 39.A square garden has an area of 2809 square m. How long is each side (in m)?
  40. 40.What is the sum of the first 26 odd numbers (1 + 3 + 5 + …)?

Answer key

  1. 2304
  2. 16
  3. 1296
  4. 22
  5. 14
  6. 900
  7. 49
  8. 324
  9. 12
  10. 12
  11. 56
  12. 324
  13. 25
  14. 225
  15. 1156
  16. 3136
  17. 1024
  18. 50
  19. 2
  20. 10
  21. 1369
  22. 1089
  23. 7225
  24. 58
  25. 84
  26. 256
  27. 1600
  28. 196
  29. 64
  30. 256
  31. 57
  32. 3600
  33. 484
  34. 3
  35. 289
  36. 16
  37. 6724
  38. 80
  39. 53
  40. 676

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