1. For comparing the cost of “fender benders” among American and Foreign produced subcompacts, a researcher in a large metropolitan area randomly samples repair bills for four makes of cars. The data are:
Mazda Toyota Focus Malibu
323 254 149 172
307 198 136 147
349 291 178 198
312 224 190 141
334 273 137 182
Mean 325 248 158 168 Grand Mean== = 224.75
SST is computed to be: 102785.75
a. Construct One Way ANOVA Table.
b. At 0.05 level of significance, perform an appropriate test by formulating the null and alternate hypotheses as it relates to the wording of this problem and interpret the results.
c. At 0.05 level of significance, conduct Fisher’s least significant difference for Toyota and Malibu repair bills.
2. One of the most difficult industries in which to maintain a long-term profit is the restaurant business. In an effort to stay abreast of changes in food preferences, a restauranteur compiles a list of menu orders. In the past, he found the following percentages in menu choices:
2013
Mexican food 14%
Seafood 12
Steak 30
Hamburgers 8
Italian 10
Chinese entrees 5
Other 21
TOTAL 100%
In a sample of 300 orders, he observes the following. Has the pattern of food selection changed? Test at 0.05 level of significance.
2014
Mexican food 54
Seafood 48
Steak 45
Hamburgers 30
Italian 36
Chinese entrees 21
Other 66
TOTAL 300
3. A gypsum manufacturer believes it average daily waste is 10.5 and a standard deviation of 4. The company has estimated that its waste is normally distributed. A consultant has randomly sampled 50 days waste and tabulated the results:
Daily waste
Category Frequency
Less than 7 2
7 3
8 4
9 7
10 10
11 3
12 4
13 5
14 3
15 or more 9
Total 50
She wants to test the hypothesis that waste is normally distributed. Using 0.05 level of significance, what should she report to the company? Please show all work.