A random sample of 250 students at a university finds that these ...

[Mr. Wonderful]

A random sample of 250 students at a university finds that these students take a mean of 14.6 credit hours per quarter with a standard deviation of 1.9 credit hours. The 90 confidence interval for the mean is 14.6+-0.198 Interpret the interval.
 
  A) 90 of the students take between 14.402 to 14.798 credit hours per quarter.
  B) The probability that a student takes 14.402 to 14.798 credit hours in a quarter is 0.90
  C) We are 90 confident that the average number of credit hours per quarter of the sampled students falls in the interval 14.402 to 14.798 hours.
  D) We are 90 confident that the average number of credit hours per quarter of students at the university falls in the interval 14.402 to 14.798 hours.

Question 2

A random sample of 250 students at a university finds that these students take a mean of 14.7 credit hours per quarter with a standard deviation of 1.9 credit hours. Estimate the mean credit hours taken by a student each quarter using a 95 confidence interval. Round to the nearest thousandth.
 
  A) 14.7  .236 B) 14.7  .015 C) 14.7  .171 D) 14.7  .011

[medine]

Answer to Question 1

D

Answer to Question 2

A