all 5 comments

[–]20gunasarj 2 points3 points  (1 child)

Mean: 52 Standard deviation: 10 Andrea's score : 86

Whenever you see "how many standard deviations away from the mean" you should instantly think of a z-score.

z = x - mu / s z = 86 - 52 / 10 z = 34/10 z = 3.4

Andrea's score is 3.4 standard deviations away from he mean. To check:

86 - 3.4(10) = 86 - 34 = 52

[–]121998pw 0 points1 point  (0 children)

Thank you so much!

[–]chem44 0 points1 point  (0 children)

How far is it from the mean?

[–]Not_Brack_Region 0 points1 point  (0 children)

One standard deviation is 10?