A consumer products testing group is evaluating two competing brands of tires, Brand 1 and Brand 2. Though the two brands have been comparable in the past, some technological advances were recently made in the Brand 2 manufacturing process, and the consumer group is testing to see if Brand 2 will outperform Brand 1. Tread wear can vary considerably depending on the type of car, and the group is trying to eliminate this effect by installing the two brands on the same random sample of  12  cars. In particular, each car has one tire of each brand on its front wheels, with half of the cars chosen at random to have Brand 1 on the left front wheel, and the rest to have Brand 2 there. After all of the cars are driven over the standard test course for  20,000  miles, the amount of tread wear (in inches) is recorded, as shown in Table 1. Car Brand 1 Brand 2 Difference(Brand 1 - Brand 2) 1 0.366 0.319 0.047 2 0.364 0.307 0.057 3 0.316 0.359 -0.043 4 0.277 0.298 -0.021 5 0.355 0.326 0.029 6 0.268 0.306 -0.038 7 0.355 0.375 -0.020 8 0.362 0.361 0.001 9 0.391 0.266 0.125 10 0.381 0.397 -0.016 11 0.394 0.337 0.057 12 0.323 0.356 -0.033 Table 1 Based on these data, can the consumer group conclude, at the  0.10  level of significance, that the mean tread wear of Brand 1 exceeds that of Brand 2? Answer this question by performing a hypothesis test regarding  μd  (which is  μ  with a letter "d" subscript), the population mean difference in tread wear for the two brands of tires. Assume that this population of differences (Brand 1 minus Brand 2) is normally distributed.     Perform a one-tailed test.   The null hypothesis: H0:   The alternative hypothesis: H1:   The type of test statistic: (Choose one)ZtChi squareF             The value of the test statistic:(Round to at least three decimal places.)   The critical value at the  0.10  level of significance:(Round to at least three decimal places.)   At the 0.10 level, can the consumer group conclude that the mean tread wear of Brand 1 exceeds that of Brand 2?   Yes     No

Holt Mcdougal Larson Pre-algebra: Student Edition 2012
1st Edition
ISBN:9780547587776
Author:HOLT MCDOUGAL
Publisher:HOLT MCDOUGAL
Chapter11: Data Analysis And Probability
Section: Chapter Questions
Problem 8CR
icon
Related questions
Question

A consumer products testing group is evaluating two competing brands of tires, Brand 1 and Brand 2. Though the two brands have been comparable in the past, some technological advances were recently made in the Brand 2 manufacturing process, and the consumer group is testing to see if Brand 2 will outperform Brand 1. Tread wear can vary considerably depending on the type of car, and the group is trying to eliminate this effect by installing the two brands on the same random sample of 

12

 cars. In particular, each car has one tire of each brand on its front wheels, with half of the cars chosen at random to have Brand 1 on the left front wheel, and the rest to have Brand 2 there. After all of the cars are driven over the standard test course for 

20,000

 miles, the amount of tread wear (in inches) is recorded, as shown in Table 1.

Car Brand 1 Brand 2 Difference
(Brand 1 - Brand 2)
1 0.366 0.319 0.047
2 0.364 0.307 0.057
3 0.316 0.359 -0.043
4 0.277 0.298 -0.021
5 0.355 0.326 0.029
6 0.268 0.306 -0.038
7 0.355 0.375 -0.020
8 0.362 0.361 0.001
9 0.391 0.266 0.125
10 0.381 0.397 -0.016
11 0.394 0.337 0.057
12 0.323 0.356 -0.033
Table 1

Based on these data, can the consumer group conclude, at the 

0.10

 level of significance, that the mean tread wear of Brand 1 exceeds that of Brand 2? Answer this question by performing a hypothesis test regarding 

μd

 (which is 

μ

 with a letter "d" subscript), the population mean difference in tread wear for the two brands of tires. Assume that this population of differences (Brand 1 minus Brand 2) is normally distributed.

 

 

Perform a one-tailed test.

 
The null hypothesis:
H0:
 
The alternative hypothesis:
H1:
 
The type of test statistic: (Choose one)ZtChi squareF      
     
The value of the test statistic:
(Round to at least three decimal places.)
 
The critical value at the 
0.10
 level of significance:
(Round to at least three decimal places.)
 
At the 0.10 level, can the consumer group conclude that the mean tread wear of Brand 1 exceeds that of Brand 2?
 
Yes
 
 
No
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 3 steps with 6 images

Blurred answer
Knowledge Booster
Anova and Design of Experiments
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, statistics and related others by exploring similar questions and additional content below.
Recommended textbooks for you
Holt Mcdougal Larson Pre-algebra: Student Edition…
Holt Mcdougal Larson Pre-algebra: Student Edition…
Algebra
ISBN:
9780547587776
Author:
HOLT MCDOUGAL
Publisher:
HOLT MCDOUGAL
College Algebra (MindTap Course List)
College Algebra (MindTap Course List)
Algebra
ISBN:
9781305652231
Author:
R. David Gustafson, Jeff Hughes
Publisher:
Cengage Learning