Question

An advertisement claims that fast food breakfast sandwiches average less than 25 grams of fat. A sample of 15 sandwiches has a mean of 23.4 grams with a standard deviation of 9 grams. Using a significance level α =0.05 is there evidence to support the claim?

What is the test statistic for this test?

Answer 1

Solution :

= 25

=23.4

S = 9

n = 15

This is the left tailed test .

The null and alternative hypothesis is ,

H0 :    = 25

Ha : < 25

Test statistic = t

= ( - ) / S / n

= (23.4 - 25) / 9 / 15

= -0.688

Test statistic = t =-0.688  

P-value =0.2512

= 0.05  

P-value >

0.2512 > 0.05

Fail to reject the null hypothesis .

There is insufficient evidence to suggest that