nogoalstoday
New member
- Joined
- Apr 4, 2014
- Messages
- 7
This is the problem:
This is what I did:
std = (xmax-xmin)/6
std = (34-25)/6
std = 1.5
n=(Z*std/B)^2
n=(1.96*1.5/.07)^2
n=1764
1764 is incorrect, not sure where I went wrong. Any help is appreciated!
| Inspection of a random sample of 34 aircraft showed that 25 needed repairs to fix a wiring problem that might compromise safety. |
| (a) | How large a sample would be needed to estimate the true proportion of jets with the wiring problem, with 95 percent confidence and an error of ± 7 percent? (Enter your answer as a whole number (no decimals). Use a z-value taken to three decimal places in your calculations.) |
std = (xmax-xmin)/6
std = (34-25)/6
std = 1.5
n=(Z*std/B)^2
n=(1.96*1.5/.07)^2
n=1764
1764 is incorrect, not sure where I went wrong. Any help is appreciated!