← Estimate divisions and square roots lesson New set →

Estimating Square Roots and Division Worksheet

Mental maths lesson 27: Estimate divisions and square roots · Set 738 · 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 1293 ÷ 44? (a) 32 (b) 3200 (c) 320
  2. 2.Best estimate of 6479 ÷ 83? (a) 8100 (b) 810 (c) 81
  3. 3.√83 to 1 decimal place? (a) 9.1 (b) 9.0 (c) 9.2 (d) 9.3
  4. 4.√37 to 1 decimal place? (a) 6.0 (b) 6.2 (c) 5.9 (d) 6.1
  5. 5.Best estimate of 1397 ÷ 69? (a) 200 (b) 2000 (c) 20
  6. 6.√43 to 1 decimal place? (a) 6.5 (b) 6.7 (c) 6.6 (d) 6.8
  7. 7.Best estimate of 3298 ÷ 51? (a) 66 (b) 6600 (c) 660
  8. 8.Best estimate of 942 ÷ 42? (a) 24 (b) 2400 (c) 240
  9. 9.√86 to 1 decimal place? (a) 9.4 (b) 9.3 (c) 9.5 (d) 9.2
  10. 10.Best estimate of 4761 ÷ 87? (a) 530 (b) 5300 (c) 53
  11. 11.√56 to 1 decimal place? (a) 7.4 (b) 7.5 (c) 7.6 (d) 7.7
  12. 12.√69 to 1 decimal place? (a) 8.4 (b) 8.3 (c) 8.5 (d) 8.6
  13. 13.Best estimate of 1839 ÷ 24? (a) 92 (b) 9200 (c) 920
  14. 14.Best estimate of 1277 ÷ 28? (a) 430 (b) 4300 (c) 43
  15. 15.Best estimate of 3617 ÷ 52? (a) 7200 (b) 720 (c) 72
  16. 16.√28 to 1 decimal place? (a) 5.3 (b) 5.2 (c) 5.1 (d) 5.0
  17. 17.Best estimate of 2095 ÷ 34? (a) 700 (b) 70 (c) 7000
  18. 18.Best estimate of 4733 ÷ 54? (a) 95 (b) 950 (c) 9500
  19. 19.Best estimate of 1633 ÷ 88? (a) 1800 (b) 180 (c) 18
  20. 20.Best estimate of 847 ÷ 66? (a) 1200 (b) 120 (c) 12
  21. 21.Best estimate of 757 ÷ 33? (a) 2500 (b) 25 (c) 250
  22. 22.Best estimate of 2170 ÷ 37? (a) 54 (b) 540 (c) 5400
  23. 23.Best estimate of 4732 ÷ 56? (a) 790 (b) 7900 (c) 79
  24. 24.Best estimate of 1896 ÷ 32? (a) 6300 (b) 63 (c) 630
  25. 25.√48 to 1 decimal place? (a) 6.6 (b) 6.7 (c) 6.9 (d) 6.8
  26. 26.Best estimate of 4604 ÷ 77? (a) 5800 (b) 58 (c) 580
  27. 27.Best estimate of 591 ÷ 33? (a) 200 (b) 20 (c) 2000
  28. 28.Best estimate of 285 ÷ 23? (a) 140 (b) 1400 (c) 14
  29. 29.Best estimate of 563 ÷ 32? (a) 190 (b) 1900 (c) 19
  30. 30.Best estimate of 4408 ÷ 62? (a) 730 (b) 73 (c) 7300
  31. 31.√59 to 1 decimal place? (a) 7.8 (b) 8.0 (c) 7.9 (d) 7.7
  32. 32.Best estimate of 2543 ÷ 46? (a) 510 (b) 5100 (c) 51
  33. 33.Best estimate of 973 ÷ 22? (a) 490 (b) 4900 (c) 49
  34. 34.Best estimate of 7496 ÷ 83? (a) 9400 (b) 940 (c) 94
  35. 35.Best estimate of 1305 ÷ 62? (a) 2200 (b) 22 (c) 220
  36. 36.Best estimate of 1539 ÷ 76? (a) 1900 (b) 19 (c) 190
  37. 37.Best estimate of 945 ÷ 26? (a) 32 (b) 320 (c) 3200
  38. 38.√92 to 1 decimal place? (a) 9.6 (b) 9.7 (c) 9.9 (d) 9.8
  39. 39.Best estimate of 1675 ÷ 63? (a) 2800 (b) 280 (c) 28
  40. 40.√85 to 1 decimal place? (a) 9.3 (b) 9.4 (c) 9.1 (d) 9.2

Answer key

  1. 32
  2. 81
  3. 9.1
  4. 6.1
  5. 20
  6. 6.6
  7. 66
  8. 24
  9. 9.3
  10. 53
  11. 7.5
  12. 8.3
  13. 92
  14. 43
  15. 72
  16. 5.3
  17. 70
  18. 95
  19. 18
  20. 12
  21. 25
  22. 54
  23. 79
  24. 63
  25. 6.9
  26. 58
  27. 20
  28. 14
  29. 19
  30. 73
  31. 7.7
  32. 51
  33. 49
  34. 94
  35. 22
  36. 19
  37. 32
  38. 9.6
  39. 28
  40. 9.2

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