31 is prime, but 39, 74 and 85 are not prime.
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∙ 2017-01-30 23:38:52The mode is the number that appears the most often. In this case it is 57.
It is 31 because it has only two factors which are itself and one
The mode, which is equivalent to the average for a set of data, is 78.4. To arrive at this answer, add all of the numbers in the data set together and divide it by ten, because there are ten test scores.
7400/85
-31
From 74 hours to 85 hours is a 14.8649% increase.
87%
6290
74 * 85 = 6290
6290
87%
The prime factors of 85 are 5, and 17 5 x 17 = 85