Question

A food scientist takes a random sample of 25 cereals in order to test the claim that the mean fiber content is less than 2.5 grams. The graphs of the data and two types of hypothesis test output are provided below. Determine which output should be used and state the conclusion of this test at the 5% significance level.

Answer 1

Choice A: there is insufficient evidence to conclude that the mean for the fiber content is less than 2.5 gms.

Explanation:

From the graphs given the more appropriate is one sample t- test

One sample t- test is used and the results are

Hypothesis Test Fiber

Sample Mean 2.62

Sample St. Dev 3.492

Degrees of Freedom 24

t- test statistic 0.1718

p- value 0.5675

the critical region for this test at ∝= 0.05 is t < -1.711

There is not enough evidence to reject the null hypothesis.

Since the calculated t= 0.1718 does not fall in the critical region the null hypothesis is accepted that the mean fiber content is not less than 2.5 grams.T