Adding Decimals
Subtracting Decimals
Figure out the rule + or -
Estimating Sums
& Differences
Adding and Subtracting Decimals
100
7.929 + 5.563
What is 13.492
100
8.27 - 3.19
What is 5.08
100
Input: 1.2 Output: 3.8
What is + 2.6
100
Estimate using rounding. 38.23 + 11.84
What is 38 + 12 = 51
100
Add the decimals 43.28 + 31.45
What is 74.73
200
1.519 + 0.92
What is 2.439
200
4.80 - 3.05
What is 1.75
200
Input: 3.5 Output: 3.2
What is - 0.3
200
Estimate using Rounding. 75.38 + 22.04
What is 75. + 22 = 97
200
Add the decimals 0.724 + 6.458
What is 7.182
300
7.60 + 10.5
18.10
300
9.43 - 7.76
What is 1.67
300
Input: 9.43 Output: 7.76
What is - 1.67
300
Estimate using Front-End Estimation 31.29 + 58.07
What is 31. + 58 = 89
300
Add the Decimals 1.325 + 0.081
What is 1.406
400
12.5 + 10.2 + 11.47
What is 34.17
400
44.06 - 40.42
3.64
400
Input:7.92 Output: 11.87
What is + 3.95
400
Estimate using clustering 12.045 + 11.81 + 12.3 + 11.56
What is 12. + 12. + 12. + 12. = 48
400
Subtract the decimals 148.93 - 121.36
What is 27.57
500
1.448 + 20.22 + 12.26
What is 33.928
500
6.7 - 0.7
6.7 - 0.7
500
Input: 8.27 Output: 3.19
What is - 5.08
500
Estimate using clustering. 6.45 + 5.88 + 5.61 + 6.03
What is 6 + 6 + 6 + 6 = 24
500
Subtract the decimals 248 - 131.48
What is 116.72
500
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