← Estimate divisions and square roots lesson New set →

Estimating Square Roots and Division Worksheet

Mental maths lesson 27: Estimate divisions and square roots · Set 221 · 40 questions
TalentJR

How to do it in your head (Guess, divide, average): Division: round the divisor to the nearest ten and find the closest multiple of it. Square root: guess the nearest whole root, then divide the number by your guess. Average the guess and the answer of the division, and round to 1 decimal place.

NameDateTime takenScore ___ / 40
  1. 1.Best estimate of 7371 ÷ 86? (a) 82 (b) 8200 (c) 820
  2. 2.Best estimate of 4845 ÷ 63? (a) 8100 (b) 810 (c) 81
  3. 3.Best estimate of 2252 ÷ 41? (a) 5600 (b) 560 (c) 56
  4. 4.Best estimate of 3523 ÷ 88? (a) 390 (b) 3900 (c) 39
  5. 5.Best estimate of 2683 ÷ 88? (a) 3000 (b) 30 (c) 300
  6. 6.Best estimate of 3855 ÷ 44? (a) 960 (b) 9600 (c) 96
  7. 7.Best estimate of 2377 ÷ 27? (a) 7900 (b) 790 (c) 79
  8. 8.√96 to 1 decimal place? (a) 9.7 (b) 9.5 (c) 9.8 (d) 9.6
  9. 9.√66 to 1 decimal place? (a) 8.1 (b) 7.9 (c) 7.8 (d) 8.0
  10. 10.√38 to 1 decimal place? (a) 6.2 (b) 6.4 (c) 6.1 (d) 6.3
  11. 11.√74 to 1 decimal place? (a) 8.5 (b) 8.4 (c) 8.6 (d) 8.3
  12. 12.√79 to 1 decimal place? (a) 9.0 (b) 9.2 (c) 9.1 (d) 8.9
  13. 13.Best estimate of 4651 ÷ 86? (a) 5200 (b) 52 (c) 520
  14. 14.Best estimate of 1763 ÷ 84? (a) 2200 (b) 22 (c) 220
  15. 15.√94 to 1 decimal place? (a) 9.9 (b) 9.7 (c) 9.8 (d) 9.6
  16. 16.√55 to 1 decimal place? (a) 7.4 (b) 7.3 (c) 7.2 (d) 7.1
  17. 17.√58 to 1 decimal place? (a) 7.4 (b) 7.5 (c) 7.6 (d) 7.3
  18. 18.Best estimate of 3031 ÷ 37? (a) 7600 (b) 760 (c) 76
  19. 19.Best estimate of 3071 ÷ 66? (a) 4400 (b) 440 (c) 44
  20. 20.√78 to 1 decimal place? (a) 8.9 (b) 8.6 (c) 8.8 (d) 8.7
  21. 21.Best estimate of 685 ÷ 24? (a) 340 (b) 3400 (c) 34
  22. 22.√48 to 1 decimal place? (a) 7.2 (b) 7.1 (c) 6.9 (d) 7.0
  23. 23.√26 to 1 decimal place? (a) 5.0 (b) 5.1 (c) 4.9 (d) 5.2
  24. 24.Best estimate of 5679 ÷ 66? (a) 81 (b) 8100 (c) 810
  25. 25.Best estimate of 1333 ÷ 32? (a) 440 (b) 4400 (c) 44
  26. 26.Best estimate of 2521 ÷ 73? (a) 36 (b) 360 (c) 3600
  27. 27.√82 to 1 decimal place? (a) 9.1 (b) 9.0 (c) 9.3 (d) 9.2
  28. 28.Best estimate of 7221 ÷ 79? (a) 9000 (b) 90 (c) 900
  29. 29.Best estimate of 1863 ÷ 21? (a) 9300 (b) 930 (c) 93
  30. 30.√37 to 1 decimal place? (a) 6.3 (b) 6.2 (c) 6.1 (d) 6.4
  31. 31.Best estimate of 1181 ÷ 59? (a) 200 (b) 20 (c) 2000
  32. 32.√24 to 1 decimal place? (a) 4.9 (b) 5.0 (c) 5.2 (d) 5.1
  33. 33.Best estimate of 3704 ÷ 43? (a) 930 (b) 9300 (c) 93
  34. 34.√31 to 1 decimal place? (a) 5.6 (b) 5.8 (c) 5.9 (d) 5.7
  35. 35.√69 to 1 decimal place? (a) 8.2 (b) 8.1 (c) 8.4 (d) 8.3
  36. 36.Best estimate of 3923 ÷ 56? (a) 6500 (b) 650 (c) 65
  37. 37.Best estimate of 2979 ÷ 72? (a) 430 (b) 4300 (c) 43
  38. 38.Best estimate of 2735 ÷ 36? (a) 68 (b) 6800 (c) 680
  39. 39.√22 to 1 decimal place? (a) 4.7 (b) 4.5 (c) 4.6 (d) 4.8
  40. 40.Best estimate of 1545 ÷ 66? (a) 22 (b) 220 (c) 2200

Answer key

  1. 82
  2. 81
  3. 56
  4. 39
  5. 30
  6. 96
  7. 79
  8. 9.8
  9. 8.1
  10. 6.2
  11. 8.6
  12. 8.9
  13. 52
  14. 22
  15. 9.7
  16. 7.4
  17. 7.6
  18. 76
  19. 44
  20. 8.8
  21. 34
  22. 6.9
  23. 5.1
  24. 81
  25. 44
  26. 36
  27. 9.1
  28. 90
  29. 93
  30. 6.1
  31. 20
  32. 4.9
  33. 93
  34. 5.6
  35. 8.3
  36. 65
  37. 43
  38. 68
  39. 4.7
  40. 22

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