In: Statistics and Probability
A film distribution manager calculates that 4% of the films released are flops.
If the manager is correct, what is the probability that the proportion of flops in a sample of 747 released films would be greater than 3%? Round your answer to four decimal places.
Answer:
Given that,
A film distribution manager calculates that 4% of the films released are flops.
If the manager is correct.
What is the probability that the proportion of flops in a sample of 747 released films would be greater than 3%:
The proportion of films released are flops:
p=4/100=0.04
The sample size: n= 747
The sample proportion follows a normal distribution with a mean and standard deviation
=0.0072 (Approximately)
The probability that the proportion of flops in a sample of 747 released films would be greater than 3%=P( > 0.03).
P( > 0.03)=1- P( 0.03)
Z-score for 0.03 is=(0.03-)/
=(0.03-0.04)/0.0072
=-0.01/0.0072
Z-score=-1.3889 (Approximately)
From standard normal tables,
P( Z -1.3889)=1- P(Z Z -1.3889)
=1-0.9177
=0.0823
P( 0.03)=P( Z -1.3889)=0.0823
P( > 0.03)=1-P( 0.03)
=1-0.0823
=0.9177
Therefore, the probability that the proportion of flops in a sample of 747 released films would be greater than 3% =0.9177.