Estimating Square Roots and Division Worksheet
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.√41 to 1 decimal place? (a) 6.2 (b) 6.5 (c) 6.3 (d) 6.4
- 2.Best estimate of 545 ÷ 34? (a) 180 (b) 1800 (c) 18
- 3.√32 to 1 decimal place? (a) 5.5 (b) 5.7 (c) 5.6 (d) 5.4
- 4.Best estimate of 1351 ÷ 36? (a) 340 (b) 3400 (c) 34
- 5.Best estimate of 578 ÷ 27? (a) 1900 (b) 190 (c) 19
- 6.√27 to 1 decimal place? (a) 4.9 (b) 5.1 (c) 5.2 (d) 5.0
- 7.Best estimate of 3855 ÷ 46? (a) 77 (b) 770 (c) 7700
- 8.Best estimate of 3594 ÷ 57? (a) 6000 (b) 60 (c) 600
- 9.√62 to 1 decimal place? (a) 7.6 (b) 7.7 (c) 7.8 (d) 7.9
- 10.√58 to 1 decimal place? (a) 7.8 (b) 7.7 (c) 7.9 (d) 7.6
- 11.Best estimate of 3726 ÷ 52? (a) 75 (b) 7500 (c) 750
- 12.Best estimate of 2256 ÷ 52? (a) 4500 (b) 45 (c) 450
- 13.Best estimate of 1964 ÷ 39? (a) 490 (b) 49 (c) 4900
- 14.Best estimate of 6328 ÷ 83? (a) 790 (b) 79 (c) 7900
- 15.Best estimate of 2914 ÷ 41? (a) 730 (b) 7300 (c) 73
- 16.√26 to 1 decimal place? (a) 5.1 (b) 5.0 (c) 5.2 (d) 4.9
- 17.Best estimate of 502 ÷ 28? (a) 170 (b) 17 (c) 1700
- 18.√37 to 1 decimal place? (a) 6.4 (b) 6.3 (c) 6.2 (d) 6.1
- 19.Best estimate of 1384 ÷ 48? (a) 28 (b) 2800 (c) 280
- 20.Best estimate of 2335 ÷ 51? (a) 4700 (b) 470 (c) 47
- 21.Best estimate of 3254 ÷ 34? (a) 10800 (b) 108 (c) 1080
- 22.Best estimate of 1718 ÷ 78? (a) 2100 (b) 210 (c) 21
- 23.√71 to 1 decimal place? (a) 8.1 (b) 8.4 (c) 8.3 (d) 8.2
- 24.Best estimate of 392 ÷ 32? (a) 1300 (b) 13 (c) 130
- 25.√44 to 1 decimal place? (a) 6.6 (b) 6.9 (c) 6.8 (d) 6.7
- 26.Best estimate of 3467 ÷ 48? (a) 6900 (b) 690 (c) 69
- 27.Best estimate of 1011 ÷ 47? (a) 20 (b) 200 (c) 2000
- 28.√94 to 1 decimal place? (a) 9.7 (b) 9.9 (c) 10.0 (d) 9.8
- 29.Best estimate of 2884 ÷ 76? (a) 36 (b) 360 (c) 3600
- 30.√43 to 1 decimal place? (a) 6.6 (b) 6.5 (c) 6.3 (d) 6.4
- 31.Best estimate of 4058 ÷ 72? (a) 580 (b) 58 (c) 5800
- 32.Best estimate of 1844 ÷ 48? (a) 3700 (b) 370 (c) 37
- 33.Best estimate of 395 ÷ 32? (a) 130 (b) 13 (c) 1300
- 34.√83 to 1 decimal place? (a) 9.0 (b) 8.9 (c) 8.8 (d) 9.1
- 35.√98 to 1 decimal place? (a) 10.1 (b) 9.9 (c) 10.0 (d) 10.2
- 36.√34 to 1 decimal place? (a) 6.0 (b) 5.9 (c) 5.7 (d) 5.8
- 37.Best estimate of 2096 ÷ 56? (a) 350 (b) 3500 (c) 35
- 38.Best estimate of 2558 ÷ 89? (a) 280 (b) 2800 (c) 28
- 39.√59 to 1 decimal place? (a) 7.6 (b) 7.8 (c) 7.7 (d) 7.9
- 40.Best estimate of 552 ÷ 24? (a) 280 (b) 2800 (c) 28
Answer key
- 6.4
- 18
- 5.7
- 34
- 19
- 5.2
- 77
- 60
- 7.9
- 7.6
- 75
- 45
- 49
- 79
- 73
- 5.1
- 17
- 6.1
- 28
- 47
- 108
- 21
- 8.4
- 13
- 6.6
- 69
- 20
- 9.7
- 36
- 6.6
- 58
- 37
- 13
- 9.1
- 9.9
- 5.8
- 35
- 28
- 7.7
- 28
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