Posted by Peter on Friday, January 9, 2009 at 10:20pm.
Maria and Zoe are taking Biology 105 but are in different classes. Maria's class has an average of 78% with a standard deviation of 5% on the midterm, whereas Zoe's class has an average of 83% with a standard deviation of 12%. Assume that scores in both classes follow a normal distribution.
A. Convert Maria's midterm score of 84 to a standard z score.
which is correct?
a. 0.083
b. 0.5
c. 0.2
d. 1.2
e. 6
B Convert Zoe's midterm score of 89 to a standard z score.
a. 1.2
b. 0.5
c. 6
d. 0.917
e. 2.2
C. Who did better relative to her class?
a. Maria
b. Zoe
c. They performed the same.
d. Neither
e. Cannot determine

Statistics  Reiny, Friday, January 9, 2009 at 10:46pm
I had maria's zscore as (8479)/5 = 1.2
and Zoe's as 0.5
what does that mean?
Whose score is closest to the class average? 
Statistics  Peter, Friday, January 9, 2009 at 10:51pm
i have no idea

Statistics  PsyDAG, Saturday, January 10, 2009 at 10:19am
Since the Z score measures deviation from the mean, the smallest Z score is closest to the mean.
I hope this helps a little more. Thanks for asking. 
Statistics  Anonymous, Thursday, July 18, 2013 at 2:57pm
c. is maria

Statistics  Anonymous, Friday, February 19, 2016 at 4:52pm
a
e 
Statistics  name, Wednesday, March 30, 2016 at 10:18am
a)= 1.2
b)=0.5
c) maria