Refer to the Journal of Food Engineering (Sep., 2013) study of the characteristics of sweet potato chips fried at different temperatures, Exercise 7.75. Recall that a sample of 6 sweet potato slices were fried at 130º using a vacuum fryer and the internal oil content (gigagrams) was measured for each slice. The results were: y̅  = .178 g/g and s = .011 g/g.

a. Conduct a test of hypothesis to determine if the standard deviation, , of the population of internal oil contents for sweet potato slices fried at 130º differs from .1. Use α = .05

b. In Exercise 7.75 you formed a 95% confidence interval for the true standard deviation of the internal oil content distribution for the sweet potato chips. Use this interval to make an inference about whether σ = .1. Does the result agree with the test, part a?

Data from Exercise 7.75

The characteristics of sweet potato chips fried at different temperatures were investigated in the Journal of Food Engineering (Sep., 2013). A sample of 6 sweet potato slices were fried at 130º using a vacuum fryer. One characteristic of interest to the researchers was internal oil content (measured in gigagrams).