| 
 
 
| Question 1103204:  In a sample of seven cars, each car was tested for nitrogen-oxide emissions (in grams per mile) and the following results were obtained:
 0.080.08,
 0.070.07,
 0.140.14,
 0.170.17,
 0.190.19,
 0.170.17,
 0.18 .0.18.
 
 
 
 Assuming that this sample is representative of the cars in use, construct a
 9898%
 confidence interval estimate of the mean amount of nitrogen-oxide emissions for all cars. If the EPA requires that nitrogen-oxide emissions be less than 0.165
 g divided by mig/mi,
 can we safely conclude that this requirement is being met?
 Answer by Boreal(15235)
      (Show Source): 
You can put this solution on YOUR website! mean is 0.1429 and s=0.0489 CI is (0.085, 0.201)
 t(df=6, 0.99) is 3.143
 half interval about the mean is +/- 3.143(.0489)/sqrt(7)=0.0581
 Because a number greater than 0.165 is in the CI, we cannot conclude that the emissions are less than 0.165 g/mg-mi
 | 
  
 | 
 |