Solution Found!
Refer to Exercise 3.92. Find the mean and variance of the
Chapter 3, Problem 94E(choose chapter or problem)
Problem 94E
Refer to Exercise 3.92. Find the mean and variance of the number of the trial on which
a the first nondefective engine is found.
b the third nondefective engine is found.
Reference
Ten percent of the engines manufactured on an assembly line are defective. If engines are randomly selected one at a time and tested, what is the probability that the first non-defective engine will be found on the second trial?
Questions & Answers
QUESTION:
Problem 94E
Refer to Exercise 3.92. Find the mean and variance of the number of the trial on which
a the first nondefective engine is found.
b the third nondefective engine is found.
Reference
Ten percent of the engines manufactured on an assembly line are defective. If engines are randomly selected one at a time and tested, what is the probability that the first non-defective engine will be found on the second trial?
ANSWER:
Solution
Step 1 of 1
a) We have to find the mean and variance of the trial when the first non-defective engine is found
Given that 10% of the engines are defective
And 90% of the engines are non defective
Then p=0.9
q=1-0.9
=0.1
Given that first non-defective engine is found
Then k=1
Mean=k/p
=1/0.9
=1.111
Variance =
=1(0.1)/(0.9)2
=0.1235