Question 266471: To test the null hypothesis that the average lifetime for a particular brand of bulb is 750 hours versus the alternative that the average lifetime is different from 750 hours, a sample of 75 bulbs is used. If the standard deviation is 50 hours and a is equal to 0.01, what values for will result in rejection of the null hypothesis. Remember to determine whether this is a one- or two-tailed test.
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! To test the null hypothesis that the average lifetime for a particular brand of bulb is 750 hours versus the alternative that the average lifetime is different from 750 hours, a sample of 75 bulbs is used.
If the standard deviation is 50 hours and a is equal to 0.01, what values for will result in rejection of the null hypothesis. Remember to determine whether this is a one- or two-tailed test.
=========
An "unequal" test is two tail.
A "less than" test is left-tail.
A "greater than" is right-tail.
-----------------
Your Problem:
Ho: u = 750
Ha: u is not equal to 750
----
critical values = ?
Find the t-values with 0.005 tails with df = 74
invT(0.005,74) = -2.6439
The CV's are -2.6439 and +2.6439
---
The rejection intervals are t< -2.6439 and t> 2.6439
=========================================================
Cheers,
Stan H.
|
|
|
