Question

A lumber company is making boards that are 2638.0 millimeters tall. If the boards are too long they must be trimmed, and if the boards are too short they cannot be used. A sample of 18 is made, and it is found that they have a mean of 2636.5 millimeters with a standard deviation of 12.0. A level of significance of 0.05 will be used to determine if the boards are either too long or too short. Assume the population distribution is approximately normal. Is there sufficient evidence to support the claim that the boards are either too long or too short

Answer 1

The answer is "Fail to reject
`H_o`, because
`w_o` is sufficient evidence for claim".

Explanation:

`H_0 \mu=2638.0 \ \ / \ \ H_a \mu \\eq 2638.0 \\\\\mu < 2638.0 \ \ or \ \ \mu > 2638.0 \\\\\alpha =0.05 \ \ level \ \ at \ \ sufficient \\\\`

Test Statistic:

`t =\frac{\bar{x}- \mu}{(S)/(√(n))}\\\\=(2636.5- 2638.0)/((12.0)/(√(18)))\\\\= -0.5303\\\\`

`dt=17\\\\`

p-value
`=0.6028`