Question

7. A study of 50 quarter pound burgers at a fast food restaurant found the mean weight of the burgers to be 0.21 lb with a standard deviation of 0.06 lbs. Use a 0.01 significance level to test the claim of the fast food restaurant that the mean weight of their quarter pound burgers is 0.25 lb.

Answer 1

Answer)

Null hypothesis Ho : u = 0.25

Alternate hypothesis Ha : u not equal to 0.25

As the population standard deviation is unknown here we will use t distribution table to conduct the test

Test statistics t = (sample mean - claimed mean)/(s.d,/√n)

t = (0.21 - 0.25)/(0.06/√50) = -4.714

Degrees of freedom is = n-1 = 49

For 49 dof and -4.714 test statistics

P-value from t distribution table is 0.00002

As the obtained p-value is less than the given significance

We reject the null hypothesis Ho

We do not have enough evidence to conclude that mean is 0.25