A company that makes cola drinks states that the mean caffeine content per 12-ounce bottle of cola 40 milligrams. You want to test this claim. During your tests, you find that a random sample of thirty 12-ounce bottles of cola has a mean caffeine content of 39.2 milligrams. Assume the population is normally distributed with a standard deviation of 7.5 milligrams. At α=0.01, can you reject the company’s claim

Claim cannot be rejected

Step-by-step explanation:

We solve this by using hypothesis testing

H0: mean = 40

H1: mean ≠ 40

We have samples of 30, but we were not gives the population standard deviation. We used the t distribution

T score = 39.2-40/(7.5/√30)

= -0.5842

Degree of freedom = 30-1 = 29

Then p value = 0.5636

In conclusion, we fail to reject the null hypothesis since 0.5636 > 0.01 significance level.

So company's claim cannot be rejected