In a study of academic procrastination, researchers reported that for a random sample of 41 undergraduate students preparing for a psychology exam, the mean time spent studying was 11.9 hours with a standard deviation of 4.5 hours. Compute a 95% confidence interval for μ, the mean time spent studying for the exam among all students taking this course.

The 95% confidence interval is  

Step-by-step explanation:

From the question we are told that

     The  sample size is  

      The  sample mean is  

       The standard deviation is  

For  a  95% confidence interval the confidence level is  95%

Given that the confidence level is 95% then the level of significance can be mathematically represented as

Next we obtain the critical values of   from the normal distribution table

     The values is

Generally the margin of error is mathematically represented as

substituting values

The 95% confidence interval is mathematically represented as

substituting values

step-by-step explanation:

where is the questions

first, we define the variables:

x: number of years after 1950

f (x): amount of vinyl sold.

then, with the variables defined, we have:

68594 vinyl records were sold in 1958 > f (8) = 68594

91299 vinyl records were sold in 1961 > f (11) = 91299

38720 vinyl records were sold in 1952 > f (2) = 38720

161743 vinyl records were sold in 1967 > f (17) = 161743

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step-by-step explanation: