← Squares and square roots lesson New set →

Class 8 Maths Worksheet: Squares and Square Roots

Maths worksheets lesson 58: Squares and square roots · Set 44 · 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.A square garden has an area of 841 square m. How long is each side (in m)?
  2. 2.How many whole numbers lie between 15² and 16²?
  3. 3.Which of these is a perfect square? (a) 1369 (b) 1394 (c) 1393
  4. 4.What is 62²? =
  5. 5.Which of these is a perfect square? (a) 500 (b) 484 (c) 522
  6. 6.What is 39²? =
  7. 7.What is 73²? =
  8. 8.What is the smallest whole number by which 243 must be divided to get a perfect square?
  9. 9.Which of these is a perfect square? (a) 1606 (b) 1600 (c) 1627
  10. 10.What is √1296? =
  11. 11.What is √3844? =
  12. 12.What is √6889? =
  13. 13.What is √121? =
  14. 14.What is the sum of the first 6 odd numbers (1 + 3 + 5 + …)?
  15. 15.What is the smallest whole number by which 504 must be multiplied to get a perfect square?
  16. 16.What is √1764? =
  17. 17.What is the sum of the first 24 odd numbers (1 + 3 + 5 + …)?
  18. 18.What is √6561? =
  19. 19.What is 16²? =
  20. 20.What is 89²? =
  21. 21.What is the smallest whole number by which 384 must be multiplied to get a perfect square?
  22. 22.How many whole numbers lie between 18² and 19²?
  23. 23.What is 77²? =
  24. 24.What is 65²? =
  25. 25.What is the smallest whole number by which 27 must be multiplied to get a perfect square?
  26. 26.How many whole numbers lie between 13² and 14²?
  27. 27.What is 68²? =
  28. 28.What is 97²? =
  29. 29.What is 76²? =
  30. 30.What is √324? =
  31. 31.How many whole numbers lie between 12² and 13²?
  32. 32.What is the sum of the first 11 odd numbers (1 + 3 + 5 + …)?
  33. 33.A square garden has an area of 256 square m. How long is each side (in m)?
  34. 34.Which of these is a perfect square? (a) 225 (b) 231 (c) 235
  35. 35.What is 48²? =
  36. 36.What is √8100? =
  37. 37.What is the sum of the first 30 odd numbers (1 + 3 + 5 + …)?
  38. 38.What is 95²? =
  39. 39.What is the smallest whole number by which 180 must be divided to get a perfect square?
  40. 40.What is √196? =

Answer key

  1. 29
  2. 30
  3. 1369
  4. 3844
  5. 484
  6. 1521
  7. 5329
  8. 3
  9. 1600
  10. 36
  11. 62
  12. 83
  13. 11
  14. 36
  15. 14
  16. 42
  17. 576
  18. 81
  19. 256
  20. 7921
  21. 6
  22. 36
  23. 5929
  24. 4225
  25. 3
  26. 26
  27. 4624
  28. 9409
  29. 5776
  30. 18
  31. 24
  32. 121
  33. 16
  34. 225
  35. 2304
  36. 90
  37. 900
  38. 9025
  39. 5
  40. 14

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