Answer:
The test to be used is the right tailed test.
Step-by-step explanation:
The type of test joe should do would be a right tailed test. This is because;
A right tailed test which we sometimes call an upper test is where the hypothesis statement contains the greater than (>) symbol. This means that, the inequality points to the right. For example, we want to compare the the life of batteries before and after a manufacturing change.
If we want to know if the battery life of maybe 90 hours would be greater than the original, then our hypothesis statements might be:
Null hypothesis: (H0 = 90).
Alternative hypothesis: (H1) > 90.
In the null hypothesis, there are no changes, but in the alternative hypothesis, the battery life in hours has increased.
So, the most important factor here is that the alternative hypothesis (H1) is what determines if we have a right tailed test, not the null hypothesis.
Thus, the test to be used is the right tailed test.
