A company compiles data on a variety of issues in education

A company compiles data on a variety of issues in education. In 1999 the company reported that the national college freshman-to-sophomore retention rate was 67%. Consider colleges with freshman classes of 700 students. Use the 68-95-99.7 rule to describe the sampling distribution model for the percentage of students expected to return for their sophomore years. Do you think the appropriate conditions are met? Which graph shows the distribution of the proportion with the intervals for 68%, 95%: and 99.7%?

Solution

Here, the mean of the distribution of proportions is 0.67.

Thus, we only consider A and D now.

However, 68-96-99.7 must be spaced like that on letter. D. Note that the 99.7% part must be very close to the ends.

Thus, it is OPTION D. [ANSWER, D]