A Random Sample of 250 Students at a University Finds $15.4$

question 70

Multiple Choice

A random sample of 250 students at a university finds that these students take a mean of $15.4$ credit hours per quarter with a standard deviation of $1.7$ credit hours. The $90 \%$ confidence interval for the mean is $15.4 \pm 0.177$ . Interpret the interval.

• A) We are \(90 \%\) confident that the average number of credit hours per quarter of students at the university falls in the interval \(15.223\) to \(15.577\) hours.
• B) The probability that a student takes \(15.223\) to \(15.577\) 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 \(15.223\) to \(15.577\) hours.
• D) \(90 \%\) of the students take between \(15.223\) to \(15.577\) credit hours per quarter.

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