In this case, we'll have to carry out several steps to find the solution.
Step 01:
Data
7.66+4.46+14.29
number 1: 7.66
number 2: 4.46
number 3: 14.29
Step 02:
Round each number to the nearest integer.
number 1: 7.66 ===> 8
number 2: 4.46 ===> 4
number 3: 14.29 ===> 14
8 + 4 + 14 = 26
7.66+4.46+14.29 = 26.41
The estimate by rounding the numbers is reasonable but not totally accurate.
That is the full solution.