On the packet of a breakfast food it indicates that on average a packet contains 600 grams of food. A food inspector believes that the packets may contain less food than this.He takes a random sample of 9 packets and weighs the food in each packet.The sample mean and variance were 59603 and 16 grams, respectively.
a. At the 1% significance level, is there sufficient evidence to support the inspector belief that on average the packets contain less than 600 grams of food?
b. What assumptions must be made to be sure that the test carried out in(a) is valid? How could you check the rwquired condition?
c. Calculate 90% confidence interval estimate for the population mean weight of food in a packet.