If it is known that the population proportion of car parks in a particular city that offer early discount fees is 25%, which of the following best describes the mean and standard deviation of the sampling distribution of the sample proportion of car parks that offer early discount fees for samples taken of size 30?
A)The mean is 0.25 and the standard deviation is 0.006.
B)The mean is 0.25 and the standard deviation is 0.75.
C)The mean is 0.25 and the standard deviation is 0.079.
D)None of these choices are correct.

Question

Quizplus · Accepted Answer

The mean of the sampling distribution of sample proportions is equal to the population proportion, which is 0.25 in this case. The standard deviation of the sampling distribution of the sample proportion can be calculated using the formula:

standard deviation = sqrt(p(1-p)/n)

where p is the population proportion and n is the sample size. Plugging in the values, we get:

standard deviation = sqrt(0.25(1-0.25)/30) = 0.079

Therefore, the best choice is C: The mean is 0.25 and the standard deviation is 0.079.

If It Is Known That the Population Proportion of Car