The mean of a certain production process is known to be 50 with a standard deviation of 2.5 .The production manager may welcome any change in mean value towards higher side but would like to safeguard...

The mean of a certain production process is known to be 50 with a standard deviation of 2.5 .The production manager may welcome any change in mean value towards higher side but would like to safeguard against decreasing values of mean.He takes a sample of 12 items that gives a mean values of 48.5.What inference should the manager take for the production process on the basis of sample results?Use 5%level of significance for the purpose