A new process for producing a type of resin is supposed to h

A new process for producing a type of resin is supposed to have a mean cycle time of 3.5 hours per batch. Six batches are produced, and their cycle times, in hours, were 3.45 3.47 3.57 3.52 3.40 3.63. Assuming that the population standard deviation is unknown, what sampling distribution should be used if the analyst is interested to make inferences about the mean cycle time required to produce the resin with the data collected from this batch of six samples? A. Z distribution B. t distribution C. chi-square distribution

Solution

Since population standard deviation is unknown, need to made inference about population mean, and sample size is too small (less than 30) so t-distirbution will be used. Since sample size is too small we cannot assume that the distribution is normally distributed.