Field tests of a low-calorie sport drink found that 80 of the 100 who tasted the beverage preferred it to the regular higher-calorie drink. A break-even analysis indicated that the launch of this product will be profitable if the beverage is preferred by more than 75% of all customers.
a) Step-by-step (please): find the p-value for a test of the null hypothesis. If alpha = .1, does the test reject null hypothesis?

Management of a chain of hotels avoids intervening in the local management of its franchises unless problems become far too common to ignore. Management believes that solving the problems is better left to the local staff unless the measure of satisfaction drops below 33%. A survey of 80 guests who recently stayed in the franchise in St. Louis found that only 20% of the guests indicated they would return to that hotel when next visiting the city. Should management intervene in the franchise in St. Louis?
a) Step-by-step (please): Find the p-value of the test. Do the data supply enough evidence to reject the null hypothesis of a = .025?