Answer:
CI =[- 4.588; 15.4]
Since the calculated value of t= 4.244 falls in the critical region so we reject H0 and conclude that we are not confident that the mean difference in lifetime between front and rear brake pads is 99.5%
Step-by-step explanation:
The given data is
Car Rear Front d= rear- front
1 40.6 32.5 8.1
2 35.4 27.1 8.3
3 46.6 35.6 11
4 47.3 35.6 11.7
5 38.7 30.3 8.4
6 51.2 41.1 10.1
7 50.6 40.7 9.9
8 45.9 34.3 11.6
<u>9 47.2 36.5 10.7</u>
∑ = 89.8
Let the hypotheses be
H0: ud= 0 against the claim Ha: ud ≠0
The degrees of freedom = n-1= 9-1= 8
The significance level is 0.05
The test statistic is
t= d`/sd/√n
The critical region is ║t║≤ t (0.025,8) = ±2.306
Sd= 7.05434553
d`=∑d/n= 89.8/9= 9.978
Therefore
t= d`/ sd/√n
t= 9.978/ 7.054/√9
t= 4.244
1) Since the calculated value of t= 4.244 falls in the critical region so we reject H0 and conclude that we are not confident that the mean difference in lifetime between front and rear brake pads is 99.5%
2) the confidence interval for the difference of two samples can be calculated by
d ` ± td sd/√n
9.978 ±2.306* 7.054/√9
- 4.588; 15.4
1 tenth(1/10) of a percent or .1%
I know this because you multiply the decimal*100 to get the percent.
Answer:
4
Step-by-step explanation:
4x4= 16
Answer:
Step-by-step explanation:
you will read the directions 2x before solving the problem then solve the problem
