A truck company wants on-time delivery for at least 98% of the parts they order from a metal manufacturing plant. They have been ordering from Hudson Manufacturing but will switch to a new, cheaper manufacturer (Steel-R-Us) unless there is evidence that this new manufacturer cannot meet the 98% on-time goal. As a test the truck company purchases a random sample of metal parts from Steel-R-Us, and then determines if these parts were delivered on-time. Which hypotheses should they test? A) H0: p 0.98 B) H0: p 0.98 HA: p = 0.98 C) H0: p = 0.98 HA: p

Question

A truck company wants on-time delivery for at least 98% of the parts they order from a metal manufacturing plant. They have been ordering from Hudson Manufacturing but will switch to a new, cheaper manufacturer (Steel-R-Us) unless there is evidence that this new manufacturer cannot meet the 98% on-time goal. As a test the truck company purchases a random sample of metal parts from Steel-R-Us, and then determines if these parts were delivered on-time. Which hypotheses should they test? A) H0: p < 0.98 HA: p > 0.98 B) H0: p > 0.98 HA: p = 0.98 C) H0: p = 0.98 HA: p < 0.98 D) H0: p < 0.98 HA: p ≠ 0.98 E) H0: p = 0.98 HA: p > 0.98

Quizplus · Accepted Answer

The null hypothesis (H0) should reflect the current situation, which is that the truck company is ordering from a supplier that meets their on-time delivery goal of at least 98%. Therefore, the H0 would be p = 0.98, indicating that the proportion of on-time deliveries from Steel-R-Us is equal to the proportion of on-time deliveries from Hudson Manufacturing. The alternative hypothesis (HA) should reflect the possibility that Steel-R-Us is not meeting the on-time delivery goal. Therefore, the HA is p < 0.98, indicating that the proportion of on-time deliveries from Steel-R-Us is less than the proportion from Hudson Manufacturing. Choice C reflects these hypotheses.

A Truck Company Wants On-Time Delivery for at Least 98