Answer: 107
Explanation:
102.3 can be rounded down to 102 (because the 3 at the end of the number is less than 5)
4.7 can be rounded up to 5 (because the 7 at the end of the number is greater than 5).
102.3 → estimate = 102
4.7 → estimate = 5
estimated sum = 107
Note that estimating the sum is NOT the same as simply adding the numbers and then rounding the sum.