Compute in excel
A college admission officer for an MBA program determines thathistorically candidates have undergraduate grade averages that arenormally distributed with standard deviation of .45. A randomsample of 25 applications from the current year yields a samplemean grade point average of 2.90. (i) Find a 95% confidenceinterval for the population mean, ?. (Round the boundaries to 2decimal places.) (ii) Based on the same sample results, astatistician computes a confidence interval for the population meanas 2.81< ? < 2.99. Find the ? for this interval and theprobability content (1- ?) as well. (Round to 4 digits.) (Note: thecorrect ? is a higher number than traditional ? used; so don’tworry if your number “looks” wrong!) Hint: first calculate ?/2using either the lower bound (2.81) or upper bound (2.99); thencalculate ?. Finally, calculate the probability content of theinterval, which is (1- ?). And make sure you use the standarderror, not the standard deviation, to calculate ?/2.
