Question

According to a recent study annual per capita consumption of milk in the United States is 21.5 gallons. Being from the Midwest, you believe milk consumption is higher there and wish to test your hypothesis. A sample of 14 individuals from the Midwestern town of Webster City was selected and then each person's milk consumption was entered into the Microsoft Excel Online file below. Use the data to set up your spreadsheet and test your hypothesis.

Given Data:

Gallons of Milk
25.5
23.84
25.25
21
17.52
19.61
19.83
26.18
34.97
30.2
28.59
20.57
26.94
27.24

1. What is a point estimate of the difference between mean annual consumption in Webster City and the national mean? ______ (2 decimals)

2. At ? = 0.05, test for a significant difference by completing the following.

Calculate the value of the test statistic (2 decimals). ______

The p-value is _______ (4 decimals)

Answer 1

= 24.80

s = 4.788

1) H₀: = 21.5

   H₁: > 21.5

= 24.80 - 21.5 = 3.3

2) The test statistic t = ()/(s/)

                               = ( 24.80 - 21.5)/(4.788/)

                              = 2.58

P-value = P(T > 2.58)

             = 1 - P(T < 2.58)

           = 1 - 0.9951 = 0.0049

Since the P-value is less than the significance level(0.0049 < 0.05), s0 we should reject H₀.

At 0.05 significance level there is sufficient evidence to conclude that milk consumption is higher than 21.5,