This should be simple, add the Amounts of snow for the first week
4.32 + 6.86 = 11.18
-------------------------------------------------------
The subtract the amounts of snow from each week
11.18 - 7.89 = 3.29
----------------------------------------
C.) 3.29 is your answer
Should be zero, I believe.
312/17
= (306+6)/ 17
= 306/17+ 6/17
= 18+ 6/17
= 18 6/17
The final answer is 18 6/17~