← Estimate divisions and square roots lesson New set →

Estimating Square Roots and Division Worksheet

Mental maths lesson 27: Estimate divisions and square roots · Set 380 · 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 1231 ÷ 32? (a) 4100 (b) 410 (c) 41
  2. 2.√65 to 1 decimal place? (a) 8.1 (b) 8.2 (c) 8.3 (d) 8.0
  3. 3.√22 to 1 decimal place? (a) 4.5 (b) 4.7 (c) 4.6 (d) 4.4
  4. 4.Best estimate of 2202 ÷ 24? (a) 1100 (b) 110 (c) 11000
  5. 5.Best estimate of 655 ÷ 22? (a) 3300 (b) 330 (c) 33
  6. 6.Best estimate of 3643 ÷ 83? (a) 460 (b) 46 (c) 4600
  7. 7.√34 to 1 decimal place? (a) 6.1 (b) 5.9 (c) 5.8 (d) 6.0
  8. 8.Best estimate of 1280 ÷ 76? (a) 1600 (b) 160 (c) 16
  9. 9.Best estimate of 2095 ÷ 26? (a) 70 (b) 700 (c) 7000
  10. 10.√86 to 1 decimal place? (a) 9.1 (b) 9.2 (c) 9.0 (d) 9.3
  11. 11.Best estimate of 390 ÷ 22? (a) 200 (b) 20 (c) 2000
  12. 12.Best estimate of 1254 ÷ 36? (a) 310 (b) 31 (c) 3100
  13. 13.√40 to 1 decimal place? (a) 6.3 (b) 6.2 (c) 6.4 (d) 6.1
  14. 14.Best estimate of 3942 ÷ 54? (a) 79 (b) 7900 (c) 790
  15. 15.Best estimate of 2263 ÷ 26? (a) 7500 (b) 75 (c) 750
  16. 16.Best estimate of 1836 ÷ 77? (a) 230 (b) 2300 (c) 23
  17. 17.Best estimate of 4832 ÷ 79? (a) 600 (b) 6000 (c) 60
  18. 18.√83 to 1 decimal place? (a) 9.2 (b) 9.0 (c) 9.3 (d) 9.1
  19. 19.√30 to 1 decimal place? (a) 5.5 (b) 5.3 (c) 5.4 (d) 5.6
  20. 20.Best estimate of 3620 ÷ 88? (a) 4000 (b) 40 (c) 400
  21. 21.√85 to 1 decimal place? (a) 9.5 (b) 9.2 (c) 9.4 (d) 9.3
  22. 22.Best estimate of 930 ÷ 54? (a) 190 (b) 19 (c) 1900
  23. 23.Best estimate of 2641 ÷ 47? (a) 53 (b) 530 (c) 5300
  24. 24.√52 to 1 decimal place? (a) 7.0 (b) 7.2 (c) 7.1 (d) 6.9
  25. 25.Best estimate of 5008 ÷ 73? (a) 7200 (b) 72 (c) 720
  26. 26.Best estimate of 2692 ÷ 61? (a) 450 (b) 4500 (c) 45
  27. 27.√74 to 1 decimal place? (a) 8.3 (b) 8.6 (c) 8.5 (d) 8.4
  28. 28.Best estimate of 863 ÷ 42? (a) 220 (b) 22 (c) 2200
  29. 29.Best estimate of 2730 ÷ 68? (a) 3900 (b) 390 (c) 39
  30. 30.√75 to 1 decimal place? (a) 8.6 (b) 8.7 (c) 8.4 (d) 8.5
  31. 31.√26 to 1 decimal place? (a) 5.0 (b) 5.1 (c) 5.3 (d) 5.2
  32. 32.√78 to 1 decimal place? (a) 8.8 (b) 8.9 (c) 9.0 (d) 8.7
  33. 33.Best estimate of 1589 ÷ 29? (a) 53 (b) 5300 (c) 530
  34. 34.Best estimate of 2356 ÷ 59? (a) 390 (b) 3900 (c) 39
  35. 35.Best estimate of 1137 ÷ 22? (a) 570 (b) 5700 (c) 57
  36. 36.√23 to 1 decimal place? (a) 4.9 (b) 5.0 (c) 4.7 (d) 4.8
  37. 37.√63 to 1 decimal place? (a) 8.2 (b) 7.9 (c) 8.1 (d) 8.0
  38. 38.√47 to 1 decimal place? (a) 7.0 (b) 6.9 (c) 7.1 (d) 6.8
  39. 39.Best estimate of 3639 ÷ 76? (a) 45 (b) 4500 (c) 450
  40. 40.Best estimate of 3442 ÷ 77? (a) 430 (b) 4300 (c) 43

Answer key

  1. 41
  2. 8.1
  3. 4.7
  4. 110
  5. 33
  6. 46
  7. 5.8
  8. 16
  9. 70
  10. 9.3
  11. 20
  12. 31
  13. 6.3
  14. 79
  15. 75
  16. 23
  17. 60
  18. 9.1
  19. 5.5
  20. 40
  21. 9.2
  22. 19
  23. 53
  24. 7.2
  25. 72
  26. 45
  27. 8.6
  28. 22
  29. 39
  30. 8.7
  31. 5.1
  32. 8.8
  33. 53
  34. 39
  35. 57
  36. 4.8
  37. 7.9
  38. 6.9
  39. 45
  40. 43

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