Question

Marshall evaluates the expression 15.3 - 7.9 and gets an answer of 7.4.

Is this a reasonable answer?
A. Since 15.3 rounds to 16 and 7.9 rounds to 8, the difference rounds to 8. His answer of 7.4 also rounds to 8, so it is reasonable.
B. Since 15.3 rounds to 16 and 7.9 rounds to 8, the difference rounds to 8. His answer of 7.4 rounds to 7, so it is not reasonable.
C. Since 15.3 rounds to 15 and 7.9 rounds to 8, the difference rounds to 7. His answer of 7.4 also rounds to 7, so it is reasonable.
D. Since 15.3 rounds to 15 and 7.9 rounds to 8, the difference rounds to 7. His answer of 7.4 is not equal to 7, so it is not reasonable.

Answer 1

C

Explanation:

Anything less than 5 rounds down while 5 and anything more rounds up. Therefore...

15.3 rounds to 15

7.9 rounds to 8

7.4 rounds to 7

So, his answer is reasonable.