Answer:
Step-by-step explanation:
A. Student estimates
10.357 to 10.4
12.062 to 12.1
7.506 to 7.1
Therefore, sum = 10.4 + 12.1 + 7.1
= 29.6 approximately it becomes 30 because we round to the nearest tens.
B. Sum without approximation gives
10.357 + 12.062 + 7.506
= 29.925
Therefore, difference becomes
Approximated value - Unapproximated value
30 - 29.925
= 0.075