Question

A student has the following grades: 86, 80, 79, 85, 70. Find the standard deviation of the grades.

Answer 1

sum (x-mean)^2
--------------
n-1

and the sqrt of that

Answer 2

or just list it in your ti83 and let it do the work

Answer 3

k

Answer 4

mean = 80
sd = 6.364 rounded

Answer 5

dang your a fast worker i struggle in math cause i jst dnt understand and get headaches from it

Answer 6

86-80 = 6, 36
80-80 = 0, 0
79-80 = 1, 1
85-80 = - 5, 25
70-80 = -10, 100
-------
162

sqrt(162/(5-1))

sqrt(162/4)

sqrt(162)/2 = 6.364 rounded :)

Answer 7

\[\frac{sum.of(x-mean)^2}{(number.of.data)-1}\]