Question

An article in the *San Jose Mercury News* stated that
students in the California state university system take 4.5 years,
on average, to finish their undergraduate degrees. Suppose you
believe that the mean time is longer. You conduct a survey of 43
students and obtain a sample mean of 5.1 with a sample standard
deviation of 1.2. Do the data support your claim at the 1%
level?

Note: If you are using a Student's *t*-distribution for the
problem, you may assume that the underlying population is normally
distributed. (In general, you must first prove that assumption,
though.)

1. State the distribution to use for the test. (Enter your
answer in the form *z* or *t*_{df}
where *df* is the degrees of freedom.)

2. What is the test statistic? (If using the *z*
distribution round your answers to two decimal places, and if using
the *t* distribution round your answers to three decimal
places.)

3. What is the *p*-value? (Round your answer to four
decimal places.)

4. (i) Alpha (Enter an exact number as an integer, fraction, or
decimal.) *α* =

5. Construct a 95% confidence interval for the true mean. Sketch the graph of the situation. Label the point estimate and the lower and upper bounds of the confidence interval. (Round your lower and upper bounds to two decimal places.)

(i) =

(ii) =

(iii) =

Answer #1

The solution to this problem is given by

An article in the San Jose Mercury News stated that students in
the California state university system take 4.5 years, on average,
to finish their undergraduate degrees. Suppose you believe that the
mean time is longer. You conduct a survey of 49 students and obtain
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the data support your claim at the 99% confidence level?

An article in the San Jose Mercury News stated that
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An article in the San Jose Mercury News stated that
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on average, to finish their undergraduate degrees. A freshman
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on average, to finish their undergraduate degrees. A freshman
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According to an article in Bloomberg Businessweek, New York
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