Answer: A. 0.50
Step-by-step explanation:
The formula to find the sample size :
, where p= Prior estimate of population proportion.
E= Margin of error
z* =Critical z-value.
When , we do not have prior estimate of population proportion , we use p= 0.5 because at p=0.5 it gives the maximum same sample size for the corresponding confidence interval and margin of error.
Therefore , the conservative value for n can be obtained by using p=0.50.
Therefore , the correct answer is A.0.50 .
Answer:
0.85
Step-by-step explanation:
Given two events A and B, the probability that either A or B occurs is given by:
where
the probability that A occurs
is the probability that B occurs
is the probability that both A and B occur at the same time
In this problem, we know the following facts:
is the probability that the car requires an oil change
is the probability that the car requires a brake repair
is the probability that the car requires both an oil change and brake repair
Therefore, the probability that either o (car requiring oil change) or b (car requiring brake repait) occur is: