120k views
1 vote
The mean annual income of certified welders is normally distributed with a mean of $50,000 and a population standard deviation of $2,000. The ship building association wishes to find out whether their welders earn more or less than $50,000 annually. The alternate hypothesis is that the mean is not $50,000. If the level of significance is .10, what is the critical value

1 Answer

5 votes

Answer: 1.645

Step-by-step explanation:

Given : The mean annual income of certified welders is normally distributed with a mean of $50,000 and a population standard deviation of $2,000.

Alternative hypothesis :
H_a:\mu\\eq50000

Since the alternative hypothesis is two-tailed , so the hypothesis test is a two-tailed test.

Also, Significance level :
\alpha=0.10

For two tailed test the to find the critical value , we need to find the z value or t-value for significance level of
\alpha/2.

The critical value will be:


z_(0.10/2)=z_(0.05)=1.645

User Bolanle
by
7.8k points