ChBE 2120 Homework 11
Due: Friday, November 19, 2010 at 5:00 PM
Note extended deadline for problem set since it was only posted Saturday afternoon
Since there is a Matlab component for this assignment, I ask that you turn in the entire
assignment via T-Square so that there is less work in collating the grading.
For problems 1-5,
you can do the work on paper or in a Word document, but if you do the work on paper, please
scan your work to PDF format.
(Scanners are available in the ChBE computer cluster and in the
computer cluster at the library.)
1.
The mean and standard deviation of the diameters of a sample of 250 rivet heads
manufactured by a company are 0.72642 in. and 0.00058 in., respectively. Find interval
estimates for the mean diameter of all rivet heads manufactured by the company at 99%,
98%, 95%, and 90% confidence levels.
2.
The sodium content of thirty 300-gram boxes of organic corn flakes was determined.
The data (in milligrams) are as follows: 131.15, 130.69, 130.91, 129.54, 129.64, 128.77,
130.72, 128.33, 128.24, 129.65, 130.14, 129.29, 128.71, 129.00, 129.39, 130.42, 129.53,
130.12, 129.78, 130.92, 131.15, 130.69, 130.91, 129.54, 129.64, 128.77, 130.72, 128.33,
128.24, 129.65.
Test the claim that the mean sodium content of this brand of cornflakes
is 130 milligrams.
Use a significance of 0.05.
3.
Tests are being conducted of an equation to predict the equilibrium vapor pressure of CO
2
for a reaction in involving a potassium carbonate solution. The actual equilibrium
pressure was measured for 9 different reactions. The experimental results and the
prediction from the equation are listed below. First, find a 95% confidence interval for
the
mean difference
(NOT the difference of means) between the estimated and actual
equilibrium pressures.
Next, test the hypothesis that the mean difference between