I need help salving for t

6. Assume that the sample has been selected from a population with a normal distribution. A manufacturer makes ball bearings that are supposed to have a mean weight of 30 gram. A retailer suspects that the mean weight is actually less than 30 gram. The mean weight for a random sample of 16 ball bearings is 29.5 gram with a standard deviation of 4.1 gram. At the 0.05 significance level, test the claim that the mean is less than 30 gram. t = X - M S Vn