A new manufacturing procedure is proposed which will reduce the current water consumption of 900 liters/cycle. A trial set of 40 manufacturing cycles using the new process has average water consumption of Xbar=884 literrs/cycle and standard deviation of the sample is s=50.6 liters/cycle. A hypothesis testing procedure is needed to make a decision about switching to the new process.
A) Formulate appropriate null and alternate hypothesis.
B) Determine the critical value of Xbar for the fixed-level test with alpha=0.05
C) Determine the P-value for the data.
D) Should the null hypothesis be rejected at the 5% level?