Susan keeps track of the number of tickets sold for each play presented at the community theater. Within how many standard deviations of th mean do all the values fall? 135, 71, 69, 80, 158, 152, 161, 96, 122, 118, 87, 85.

3
4
5
2

2 answers

Find the mean first = sum of scores/number of scores

Subtract each of the scores from the mean and square each difference. Find the sum of these squares. Divide that by the number of scores to get variance.

Standard deviation = square root of variance

I'll let you do the calculations.
I keep coming up with 1 as the answer and that's not a choice?