statistics

[pboland]

You have just completed grading the final exams for your biology class and find that the mean scores are 100 with a standard deviation (SD) of 15 with a variance equal to 225. If one student has a score of 115, what is the student's SD as compared to the rest of the class?
a. One SD below the mean
b. 15 SD above the mean
c. Two SD above the mean
d. One SD above the mean
I ahve just started this class and need alittle help.

 

[tkhunny]

Calculate the Z-score.

(Score - Mean)/(Standard Deviation) = (115-100)/15 = 15/15 = 1

One (1) SD Above the Mean.

There. Your official free push.