Chicken Delight claims that 84 percent of its orders are delivered within 10 minutes of the time the order is placed. A sample of 80 orders revealed that 63 were delivered within the promised time. At the .10 significance level, can we conclude that less than 84 percent of the orders are delivered in less than 10 minutes?
(a) What is the decision rule? (Negative amount should be indicated by a minus sign. Round your answer to 2 decimal places.)
(b) Compute the value of the test statistic. (Negative amount should be indicated by a minus sign. Round sample proportion to 2 decimal places. Round your answer to 2 decimal places.)