SOLVE THE BELOW QUESTIONS USING EXCEL FORMULAS NOTE THAT THE DATA RANGE IS NAMES AS hour

A company that produces cell phones claims its standard phone battery lasts longer on average than other batteries in the market. The company claims that their batteries on average lasts more than 31 hours.

To support this claim, the company took a sample of 100 cellphones and recorded the hours that their batteries last.

a) Calculate the sample size (using an appropriate formula), the sample average and standard deviation, and the alpha value given that the required confidence level is 95% (all the remaining parts will use this same confidence level).

b) Evaluatethecompanysclaim,usingthefollowingmethodsandcompareyourresultsof each method. Make your managerial conclusions in a few sentences, written on your Excel sheet.

Confidence interval

Critical value

P-value

c) The company is also interested in knowing the proportion of the phone batteries that last over 31 hours. They would like to test this claim and see if this proportion is over 75%. Carry out the analysis for the company, using the method of your choice and write your conclusions.