Question

Find the range and the standard deviation (correct to two decimal places).

83,96,100,100,103
find the range and standard deviation

Do I that 5 numbers add that divide by 5
for the range I am not sure how to do standard deviation. Thank you

Answer 1

add and divide by 5 gives the mean, not the range

the range is hi-low = 103-83=20

The mean is 96.4
To find the std,

(1) take the difference of each value from the mean
(2) square that difference
(3) add up all those squares
(4) take the square root.
That is the std.

Better review that section again. Visit

http://www.mathsisfun.com/data/standard-deviation.html

for a nice simple explanation and example.

Answer 2

thank you Steve it is appreciated. Thank you very much for the site.

Answer 3

Five staff members have been working in a convenience store for 4, 5, X, 5 and 4 years respectively. Given that the mean of their working experiences is 4.6, find the population standard deviation. (correct to 2 decimal places)