Question

How do I get the P value for this problem? ...

In a General Social Survey, respondents working full time or part time reported how many hours they worked in the previous week at all jobs. The random sample of 1,729 produced a mean of 41.8 hours with a standard deviation of 14.6 hours. Using these data what would you conclude in a test of the following hypothesis?

Ho: M = 40 hours

Ha: M > 40 hours

The teacher told me the p value is very small (less than 0.0001) and therefore I should reject the null hypothesis, but every time I calculate the test statistic I get 5.13 and then I check on the P value calculator and it tells me that a right tailed test with this produces a probability of 0.993996. That seems like a huge probability to me. Please help me understand what I am doing wrong and how to find the correct P value for this problem. I'm not sure if I'm calculating the test statistic wrong or not flipping the probability to a negative since the z distribution only gives probabilities to the left? I'm very confused. Please help.  Thanks

Answer 1