statistics and probability

Directions: Read and analyze each problem. On the table below, put a check on the columns of the criteria that correspond to the given problem. 1.It is claimed that the average age of working students in a certain university is 35. A researcher selected a random sample of 25 working students. The computation of their ages resulted to an average of 32 years with standard deviation of 10 years. 2. A manufacturer of tires claim that their tire has a mean life of at least 50,000kms. A random sample of 28 of these tires is tested and the sample mean is 33,000kms. Assume that the population standard deviation is 3,000kms and the lives of the tires are approximately normally distributed. 3. On average, a drinking vending machine is adjusted so it dispenses 240ml of fruit juice. However, he machine tends to go out of adjustment and periodic checks are made to determine the average mount of fruit juice being dispensed. A sample of 28 with a standard deviation of 15ml in plastic cup drinks is taken to test the adjustment of the machine. n > 30 n