← Squares and square roots lesson New set →

Class 8 Maths Worksheet: Squares and Square Roots

Maths worksheets lesson 58: Squares and square roots · Set 77 · 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.Which of these is a perfect square? (a) 125 (b) 121 (c) 132
  2. 2.What is √5929? =
  3. 3.Which of these is a perfect square? (a) 1625 (b) 1600 (c) 1649
  4. 4.What is √3969? =
  5. 5.How many whole numbers lie between 34² and 35²?
  6. 6.What is √4489? =
  7. 7.Which of these is a perfect square? (a) 281 (b) 274 (c) 256
  8. 8.What is √8836? =
  9. 9.What is the smallest whole number by which 396 must be divided to get a perfect square?
  10. 10.Which of these is a perfect square? (a) 486 (b) 521 (c) 484
  11. 11.What is √1600? =
  12. 12.What is the sum of the first 17 odd numbers (1 + 3 + 5 + …)?
  13. 13.What is the smallest whole number by which 208 must be multiplied to get a perfect square?
  14. 14.What is the smallest whole number by which 18 must be multiplied to get a perfect square?
  15. 15.What is 77²? =
  16. 16.What is the sum of the first 24 odd numbers (1 + 3 + 5 + …)?
  17. 17.Which of these is a perfect square? (a) 529 (b) 549 (c) 553
  18. 18.Which of these is a perfect square? (a) 625 (b) 632 (c) 634
  19. 19.What is √1296? =
  20. 20.A square garden has an area of 225 square m. How long is each side (in m)?
  21. 21.What is 39²? =
  22. 22.What is √3844? =
  23. 23.What is the smallest whole number by which 704 must be multiplied to get a perfect square?
  24. 24.How many whole numbers lie between 35² and 36²?
  25. 25.What is 15²? =
  26. 26.What is the smallest whole number by which 891 must be multiplied to get a perfect square?
  27. 27.Which of these is a perfect square? (a) 203 (b) 221 (c) 196
  28. 28.A square garden has an area of 36 square m. How long is each side (in m)?
  29. 29.Which of these is a perfect square? (a) 1180 (b) 1156 (c) 1160
  30. 30.How many whole numbers lie between 17² and 18²?
  31. 31.What is √729? =
  32. 32.How many whole numbers lie between 44² and 45²?
  33. 33.What is √1681? =
  34. 34.What is 33²? =
  35. 35.How many whole numbers lie between 23² and 24²?
  36. 36.What is the sum of the first 25 odd numbers (1 + 3 + 5 + …)?
  37. 37.What is √256? =
  38. 38.What is the smallest whole number by which 243 must be multiplied to get a perfect square?
  39. 39.What is 93²? =
  40. 40.Which of these is a perfect square? (a) 743 (b) 781 (c) 729

Answer key

  1. 121
  2. 77
  3. 1600
  4. 63
  5. 68
  6. 67
  7. 256
  8. 94
  9. 11
  10. 484
  11. 40
  12. 289
  13. 13
  14. 2
  15. 5929
  16. 576
  17. 529
  18. 625
  19. 36
  20. 15
  21. 1521
  22. 62
  23. 11
  24. 70
  25. 225
  26. 11
  27. 196
  28. 6
  29. 1156
  30. 34
  31. 27
  32. 88
  33. 41
  34. 1089
  35. 46
  36. 625
  37. 16
  38. 3
  39. 8649
  40. 729

Free maths worksheets lessons, practice and worksheets at talentjr.in/maths-worksheets