Confidence Interval for single proportion.
A study was conducted to investigate drinking problems among college students. In 1983, a group of students were asked whether they had ever driven an automobile as drinking. In 1987 after legal drinking age was raised, a different group of college students were asked the same question. The results are as follows.
|
Drove While Drinking
|
Year
|
Total
|
|
1983
|
1987
|
|
Yes
|
1250
|
991
|
2241
|
|
No
|
1387
|
1666
|
3053
|
|
Total
|
2637
|
2657
|
5294
|
Compute separately for 1983 and 1987, the 95% confidence interval for the proportion of students who had driven an automobile while drinking.