Because of high production-changeover time and costs, a director of manufacturing must convince management that a proposed manufacturing method reduces costs before the new method can be implemented. The current production method operates with a mean cost of per hour. A research study will measure the cost of the new method over a sample production period.

This question is incomplete, here is the complete question:

Because of high production-changeover time and costs, a director of manufacturing must convince management that a proposed manufacturing method reduces costs before the new method can be implemented. The current production method operates with a mean cost of $\$ 220$ per hour. A research study will measure the cost of the new method over a sample production period.

a. Develop the null and alternative hypotheses most appropriate for this study.

b. Comment on the conclusion when $H_{0}$ cannot be rejected.

c. Comment on the conclusion when $H_{0}$ can be rejected.

Check the explanation

Explanation:

The above information states that the mean cost is $220 per hour.

Here, the director of manufacturing unit must persuade the management and also proposed a manufacturing technique that reduces cost before the latest method can be put into practice. This can be written as μ<220. The balance of the claim is µ≥220. In this given experiment, the alternative hypothesis point toward this solution

$H_{0} : \mu \geq 220, H_{a} : \mu<220$

b. There is not enough evidence to maintain the claim that the proposed

manufacturing technique reduces costs.

c. There is adequate evidence to support the assertion that the proposed

manufacturing method decreases costs.