First, you need to find 30÷5 and 30÷6. You do this because you need to know the multiplier when you create an equivalent fraction. 30÷5 is 6 and 30÷6 is 5. 2 1/5. You need to multiply the 1 and 5 by 6, that is 2 6/30. 1 5/6. 5 and 6 multiplied by 5 is 25 and 30. 1 5/6=1 25/30
Entering the numbers into a list lets a calculator do the work of this. The mode is 74, as that is the only value that appears more than once.
mean: 89 median: 87.5 . . . . . the average of the middle two numbers, 87, 88 mode: 74 range: 67–119, a difference of 52 variance: 243.4 . . . . . the square of the sd, or the difference of mean square and square of the mean standard deviation: ≈ 15.6