6,290
31 is prime, but 39, 74 and 85 are not prime.
7400/85
From 74 hours to 85 hours is a 14.8649% increase.
87%
6290
74 * 85 = 6290
87%
The mode is the number that appears the most often. In this case it is 57.
-91
74 multiplied by 85 is 6,290.
It is 74/3 times 3 = 74