As a market researcher you have been hired by a fast food ch

As a market researcher, you have been hired by a fast food chain. They want to know what kind of food containers the public prefers (given environmental and recycling concerns). The question is whether the public prefers their hamburgers wrapped in aluminum foil, foam boxes, or paper. Analyze the following data for whether there is a significant difference.

A. Which statistical test is appropriate?

B. State hypothesis in symbols and words

Ho:

H1:

C. Calculate:

a. critical value

b. test statistic

c. make a decision

d. state a conclusion using the correct form

Solution

Here we use t-test because sample information is given.

Hypothesis for the test is,

H0 : mu =0 Vs H1 : mu 0

Assume alpha = 0.05

critical value we can find by using EXCEL.

=tinv(probability, d.f.)

probability = 0.05

d.f. = n - 1 = 3-1 = 2

tc = 4.3027

The test statistic is,

t = (Xbar - mu) / [ s/sqrt(n) ]

Where Xbar is mean of 3 observations.

s is standard deviation of 3 observations.

Xbar = (123 + 74 + 103) / 3 = 100

s = sqrt [ 1/n-1 * (X-Xbar)² = 24.6374

t = (100 - 0) / [24.6374/sqrt(3) ]

t = 100 / 14.2244

t = 7.0302

t > tc

reject H0 at 5% level of significance.

Conclusion : Population mean is differ than 0.