Chapter 6.4, Problem 8E

As part of the quality-control program for a catalyst manufacturing line, the raw materials (alumina and a binder) are tested for purity. The process requires that the purity of the alumina be greater than 85%. A random sample from a recent shipment of alumina yielded the following results (in percent):

93.2    87.0    92.1    90.1    87.3    93.6

A hypothesis test will be done to determine whether or not to accept the shipment.

a.    State the appropriate null and alternate hypotheses.

b.    Compute the P-value.

c.    Should the shipment be accepted? Explain.