Question

95% confidence interval (PART C)

When a company advertises on the Internet, the company pays the operators of search engines each time an ad for the company appears with search results and someone clicks on the link. Click fraud is when a computer program pretending to be a customer clicks on the link. An analysis of 1,100 clicks coming into a company's site during a week identified 155 of these clicks as fraudulent. Complete parts (a) through (c) below. □ A. □ B. The clicks must be selected at random. The week must be randomly selected. C. The company must be representative of all companies that advertise on the Intenet. D. The week must be representative of a typical week ldentify the population below 0 A. O B. ° C. All companies that advertise on the Internet All clicks on ads placed in search results A fraudulent clicks D. All dlicks into this company's site (b Show the 95% confidence interval for the population proportion of fraudulent clicks in a form suitable for sharing with a no technical audience. The 95% confidence interval for the population proportion is [12% to 16 %) Round to one decimal place as needed.) (c)If a company pays the operators of a search engine $425 for oach click, give a 95% confidence interval for the mean cost per dick due to fraud The 95% confidence interval for the mean cost isK1to4D (Round to the nearest cent as needed.)

Answer 1

Part C)

We have already find the 95% confidence interval of the population proportion in part b)

The confidence interval for the population proportion is ( 12 %, 16.1%)

In part c) we have to find a 95% confidence interval for the mean.

Required cost for the mean at $4.25.

n = 1100

Lower limit = *n = 0.12*1100*4.25 = 561

Upper limit = *n = 0.161*1100*4.25 = 752.68

The 95% confidence interval for the mean cost is $561 to $752.68