← Squares and square roots lesson New set →

Class 8 Maths Worksheet: Squares and Square Roots

Maths worksheets lesson 58: Squares and square roots · Set 88 · 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.How many whole numbers lie between 11² and 12²?
  2. 2.What is the smallest whole number by which 27 must be divided to get a perfect square?
  3. 3.Which of these is a perfect square? (a) 121 (b) 131 (c) 126
  4. 4.What is the sum of the first 29 odd numbers (1 + 3 + 5 + …)?
  5. 5.How many whole numbers lie between 49² and 50²?
  6. 6.Which of these is a perfect square? (a) 109 (b) 100 (c) 112
  7. 7.What is √7921? =
  8. 8.What is √3600? =
  9. 9.What is 61²? =
  10. 10.How many whole numbers lie between 43² and 44²?
  11. 11.A square garden has an area of 3481 square m. How long is each side (in m)?
  12. 12.What is 31²? =
  13. 13.What is the sum of the first 30 odd numbers (1 + 3 + 5 + …)?
  14. 14.What is √529? =
  15. 15.What is 98²? =
  16. 16.What is the smallest whole number by which 160 must be multiplied to get a perfect square?
  17. 17.What is √841? =
  18. 18.What is the sum of the first 13 odd numbers (1 + 3 + 5 + …)?
  19. 19.Which of these is a perfect square? (a) 1584 (b) 1521 (c) 1544
  20. 20.What is 17²? =
  21. 21.What is √4356? =
  22. 22.What is 78²? =
  23. 23.A square garden has an area of 484 square m. How long is each side (in m)?
  24. 24.Which of these is a perfect square? (a) 1388 (b) 1369 (c) 1387
  25. 25.What is 90²? =
  26. 26.How many whole numbers lie between 25² and 26²?
  27. 27.How many whole numbers lie between 37² and 38²?
  28. 28.What is √1936? =
  29. 29.A square garden has an area of 1764 square m. How long is each side (in m)?
  30. 30.What is √7225? =
  31. 31.What is the sum of the first 28 odd numbers (1 + 3 + 5 + …)?
  32. 32.Which of these is a perfect square? (a) 951 (b) 900 (c) 912
  33. 33.What is 52²? =
  34. 34.What is the smallest whole number by which 320 must be divided to get a perfect square?
  35. 35.What is the sum of the first 11 odd numbers (1 + 3 + 5 + …)?
  36. 36.What is 37²? =
  37. 37.What is the sum of the first 17 odd numbers (1 + 3 + 5 + …)?
  38. 38.A square garden has an area of 625 square m. How long is each side (in m)?
  39. 39.How many whole numbers lie between 40² and 41²?
  40. 40.A square garden has an area of 841 square m. How long is each side (in m)?

Answer key

  1. 22
  2. 3
  3. 121
  4. 841
  5. 98
  6. 100
  7. 89
  8. 60
  9. 3721
  10. 86
  11. 59
  12. 961
  13. 900
  14. 23
  15. 9604
  16. 10
  17. 29
  18. 169
  19. 1521
  20. 289
  21. 66
  22. 6084
  23. 22
  24. 1369
  25. 8100
  26. 50
  27. 74
  28. 44
  29. 42
  30. 85
  31. 784
  32. 900
  33. 2704
  34. 5
  35. 121
  36. 1369
  37. 289
  38. 25
  39. 80
  40. 29

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