← Squares and square roots lesson New set →

Class 8 Maths Worksheet: Squares and Square Roots

Maths worksheets lesson 58: Squares and square roots · Set 629 · 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) 1101 (b) 1124 (c) 1089
  2. 2.What is 34²? =
  3. 3.What is √4624? =
  4. 4.Which of these is a perfect square? (a) 435 (b) 412 (c) 400
  5. 5.What is the smallest whole number by which 640 must be multiplied to get a perfect square?
  6. 6.What is the smallest whole number by which 40 must be divided to get a perfect square?
  7. 7.What is √5625? =
  8. 8.What is the sum of the first 17 odd numbers (1 + 3 + 5 + …)?
  9. 9.What is √8100? =
  10. 10.A square garden has an area of 324 square m. How long is each side (in m)?
  11. 11.What is 63²? =
  12. 12.A square garden has an area of 784 square m. How long is each side (in m)?
  13. 13.What is 99²? =
  14. 14.What is the sum of the first 18 odd numbers (1 + 3 + 5 + …)?
  15. 15.What is the sum of the first 25 odd numbers (1 + 3 + 5 + …)?
  16. 16.What is the sum of the first 20 odd numbers (1 + 3 + 5 + …)?
  17. 17.How many whole numbers lie between 38² and 39²?
  18. 18.How many whole numbers lie between 30² and 31²?
  19. 19.What is 89²? =
  20. 20.What is the sum of the first 23 odd numbers (1 + 3 + 5 + …)?
  21. 21.What is the smallest whole number by which 350 must be multiplied to get a perfect square?
  22. 22.What is 72²? =
  23. 23.What is the sum of the first 15 odd numbers (1 + 3 + 5 + …)?
  24. 24.What is the sum of the first 11 odd numbers (1 + 3 + 5 + …)?
  25. 25.Which of these is a perfect square? (a) 173 (b) 169 (c) 181
  26. 26.What is √400? =
  27. 27.What is the smallest whole number by which 8 must be divided to get a perfect square?
  28. 28.Which of these is a perfect square? (a) 222 (b) 200 (c) 196
  29. 29.What is √784? =
  30. 30.Which of these is a perfect square? (a) 650 (b) 625 (c) 652
  31. 31.How many whole numbers lie between 34² and 35²?
  32. 32.What is the smallest whole number by which 12 must be multiplied to get a perfect square?
  33. 33.What is √8464? =
  34. 34.What is √3721? =
  35. 35.How many whole numbers lie between 36² and 37²?
  36. 36.What is 40²? =
  37. 37.A square garden has an area of 225 square m. How long is each side (in m)?
  38. 38.How many whole numbers lie between 26² and 27²?
  39. 39.What is the sum of the first 9 odd numbers (1 + 3 + 5 + …)?
  40. 40.What is √6724? =

Answer key

  1. 1089
  2. 1156
  3. 68
  4. 400
  5. 10
  6. 10
  7. 75
  8. 289
  9. 90
  10. 18
  11. 3969
  12. 28
  13. 9801
  14. 324
  15. 625
  16. 400
  17. 76
  18. 60
  19. 7921
  20. 529
  21. 14
  22. 5184
  23. 225
  24. 121
  25. 169
  26. 20
  27. 2
  28. 196
  29. 28
  30. 625
  31. 68
  32. 3
  33. 92
  34. 61
  35. 72
  36. 1600
  37. 15
  38. 52
  39. 81
  40. 82

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