OMGT6123 Statistics & Probability Example 2 ProbSet

This is the Statistics & Probability Example 2 Problem Set for OMGT6123.  Please peruse the video tutorial of the solution posted to the course website. 


OMGT6123 Expected Values & Standard Normal Distribution Examples

 

1.         Sammy's grades are distributed as follows:

 

Grade

Proportion of Grade Type

Grade Points per Grade Type

A

1/2

4

B

1/3

3

C+

1/10

2.3

C

1/10

2

 

            All grade types are the same number of class hours (e.g., all are 3-hour classes).  Calculate Sammy's current GPA & the current grade standard deviation.  Comment on Sammy's current GPA.

 

 

2.         Sabrina knows her sales #'s could increase as follows & believes that each growth # is equally weighted.  However, Josey her co-owner thinks the growth #'s are weighted as noted below.  Help Sabrina & Josey calculate the expected growth based on both their probability distributions & comment on how they are similar or different.

 

Growth #

Josey's Probability of Growth # [i.e., P(growth)]

5

47%

3

23%

2

15%

0

15%

 

 

3.         Bill knows the mean of his customer service process is 40 minutes and the standard deviation is 5 minutes and is normally distributed.  He wishes to know at what service process value does he take care of 95% of his customers.

 

 

 

 

4.         Bill's colleague explains that if Bill could cut his service process standard deviation in half he would reach almost all (99+%) of his customers in under 47 minutes.  Is this true?