An online retailer has a new website and would like to compare the proportion of customers who made a purchase from the old website versus the proportion who made a purchase from the new website to see if the two proportions are different. A simple random sample of customers visiting the old and new websites is taken. The results are shown below. Old site New site Successes Observations Proportion 156 Successes 400 Observations 0.390 Proportion Confidence level 90% z-score 1.819 p-value 0.069 49 100 0.490 p=Ex: 1.234 -3 -2 -1 0 1 2 3 x = Ex: 1.234 x = Old site samples: nold Ex: 9 New site samples: nnew Sample proportion for old site samples: Dold = Ex: 1.234 Sample proportion for new site samples: new