A professor has a 95% passing rate for all of his past classes. He surveys his...
- A professor has a 95% passing rate for all of his past classes. He surveys his current 93 students, and 13 of them are worried about failing.
- For his class of 93 students, determine the mean and standard deviation of students passing the class.
Homework Answers
Solution :
Given that,
p = 0.95
q = 1 - p = 1 - 0.95 = 0.05
n = 93
Using binomial distribution,
Mean = 
= n * p = 93 * 0.95 = 88.35
Standard deviation = 
= 
n * p * q =
93 * 0.95 * 0.05 = 2.10
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