Question

Find the standard deviation of the given data rounded to the nearest hundredth.3, 4, 5, 7, 10, 12, 15

Answer 1

4.140393356

Explanation:

Mean = (3+4+5+7+10+12+15) / 7 = 8

Count = 7 numbers

Sum of the numbers = 56

Each number minus the mean =

(3-8=-5)(4-8=-4)(5-8=-3)(7-8=-1)(10-8=2)(12-8=4)(15-8=7)

Now square of each of these numbers:

25+16+9+1+4+16+49 = 120

Variance = 120/7 = 17.14285714

Standard deviation = square root of the variance

Sqrt 17.14285714 = 4.140393356