MINITAB Lab Final Math 1103 Name_____________________
Sample
Directions: Use MINITAB to create statistical output that will answer the following questions. Label each question of output before entering the appropriate commands. Write your answers on this sheet of paper. Please submit your disc and this sheet for grading when you are finished. (I promise to return your disc by the end of the week.)
When you are finished, you might want to save your session window under an appropriate file name.
PROBLEM 1 (12 points)
Some data was collected the first week of class from various Math 1103 classes over the past several years and is saved in a worksheet file called statsurv.mtw. This file is located on the l:-drive directory in folder mmarzin. If you have trouble locating this file ask me for help! Each student was asked their Gender, length of one-way Commute (in miles), GPA, number of Credits they were currently taking, the Grade they expected to get in the class, and their Political preference.
Using the variable Commute, find the following descriptive statistics:
a) mean = __________ b) median = __________ c) sample standard deviation = _____________
d) Circle the shape which best describes the distribution of the students’ commute lengths:
BELL-SHAPED UNIFORM SKEW-LEFT SKEW-RIGHT
e) Half of the students from the survey commuted at least how many miles? ____________
f) What percent of the females expected to get an A? _____________
PROBLEM 2 (9 points)
Use MINITAB commands to simulate rolling three standard six-sided dice 500 times. Create a column that sums the three dice.
A) Save this worksheet and call it “the first 8 letters of your last name”. (If you need help ----ASK!!)
What was the first sum obtained? _______________
B) What sum occurred the most often? ___________.
C) What percent of the time did a sum of 3 occur? ______________.
PROBLEM 3 (14 points)
Please open the file Homes.mtw that can be found in the k:/Mtbwin/Student9 directory. This data set contains real estate data on 150 randomly selected homes. The price is in dollars, the area of the house is expressed in square feet, the number of acres is stored in column 3, the number of rooms in the house is stored in column 4 and the number of bathrooms in the house is stored in column 5.
A) Find a 98% confidence interval for the mean price of a home based on this survey. __________________________
B) What is the point estimate for your interval in part (A)? ________________
C) Now you will test the claim that a linear relationship exists between the area of a home and its price.
i) State the hypotheses: H0: _______________________
H1: _______________________
ii) r = ____________
iii) State the conclusion in nontechnical terms. (Assume you are using a 5% significance level.)
D) Based on your results above, what is the best prediction for the price of a house that has 1600 square feet of area?
[Note that you may need to find the regression equation to answer this question]
PROBLEM 4 (6 points)
A machine is set to fill 1-liter milk bottles. The fills are normally distributed with a mean of 1.04 liters and a standard deviation of 0.05 liters.
A) What percent of the bottles will have more than 1.0 liters of milk? ___________________
B) Find the value below which the smallest 10% of the fills occurs. ________________
PROBLEM 5 (6 points)
A national study indicate that 63% of all Americans who travel by car look for gas and food outlets that are close to or visible from the highway. A random sample of 15 Americans who travel by car is taken.
A) What is the probability that all 15 look for gas and food that is close or visible from the highway? _____________
B) What is the probability that less than five Americans from the sample look for gas and food that is close or visible from the highway? ______________
PROBLEM 6 (11 points)
A Pennsylvania medical center collected some data on the blood cholesterol levels of heart-attack patients. A total of 28 heart-attack patients had their cholesterol levels measured two days after the attack, four days after the attack, and 14 days after. In addition, cholesterol levels were recorded for a control group of 30 people who had not had a heart attack. This data is saved in a worksheet file called Cholest.mtw. This file is located on l:/Mmarzin. If you have trouble locating this file ask me for help! Assume all distributions are approximately normal.
You will be testing the claim cholesterol levels return to normal by four days after a heart attack by comparing the 4-day variable with the control group.
A) Which test for means is this? (CIRCLE ONE) DEPENDENT INDEPENDENT
B) State the Null and Alternative hypothesis: Ho: ___________________
H1: ___________________
B) Are you supposed to ‘pool’ the standard deviation? (Circle one) YES or NO
C) State the p-value for the test: _______________
D) State your conclusion in nontechnical terms if you use a 1% significance level:
PROBLEM 7 (12 points)
An article in the Washington Post stated that nearly 45% of the U.S. population is born with brown eyes, although they don’t necessarily stay that way. To test the newspaper’s claim, a random sample of 80 people was selected, and 32 had brown eyes. Is there sufficient evidence to dispute the newspaper’s claim regarding the brown-eyed people in the U.S.?
A) State the hypotheses: Ho: ___________________
H1: ___________________
B) State the p-value of the test __________________
C) State the conclusion in nontechnical terms if you use a 1% significance level:
D) Construct a 96% confidence interval for the proportion of the U.S. population that has brown eyes.
State your answer here:
PROBLEM 8 (9 points)
A researcher believes that the fraction of Republicans in favor of the death penalty is greater than the fraction of Democrats in favor of the death penalty. She acquired independent random samples of 200 Republicans and 200 Democrats and found that 46 Republicans and 34 Democrats favored the death penalty. Does this data support the researcher’s belief?
A) State the hypotheses: Ho: ___________________
H1: ___________________
B) State the p-value of the test __________________
C) State the conclusion in nontechnical terms if you use a 5% significance level: