# Math Help - Hypothesis test for µ

1. ## Hypothesis test for µ

Hello,
I have this question...
The driver of a suburu wishes to compare the fuel consumption of his car to the figure stated by the Automobile association as appropriate for his size car, which is 11.26km/L. Test whether or not his fuel consumption is worse than the recommended value for his size car.
Here's the data for the suburu driver..
mean = 10.10
sd = 1.05
n = 30

I've written the hypotheses down... but when I come to the test statistic, I end up with the answer 6.05? Is that right? For some reason I thought it couldn't be that large?

2. I get -6.051030159 and you probably should use a t density with 29 dfs.
I don't know if we can assume normality or not.
If you can't, then you approximate this with a standard normal via the CLT.

Your alternative hypothesis is $H_a:\mu <11.26$