# Statistics

From random sample of 200 college students, 40 students indicated that they smoke cigarettes. Use the information from the sample to calculate a 95% confidence interval for the population proportion of college students that smoke cigarettes (round to nearest hundredth).

A. (0.14, 0.26)
B. (38, 42)
C. (0.17, 0.23)
D. (0.16, 0.24)

1. Formula:

CI95 = p ± (1.96)[√(pq/n)]
...where p = x/n, q = 1 - p, and n = sample size.
Note: ± 1.96 represents 95% confidence interval using a z-table.

For p in your problem: 40/200 = 0.2
For q: 1 - p = 1 - 0.2 = 0.8
n = 200

I let you take it from here to calculate the interval and determine your answer from the selections given.

posted by MathGuru

First Name

## Similar Questions

1. ### Statistics

Suppose that 30% of all college students smoke cigarettes. A sample of 18 is selected randomly. What is the probability that exactly 10 students smoke? Round your answer to four decimal places.
2. ### statistics

In a random sample of 112 State College students, 41 students reported being current smokers. a) Calculate the 95% confidence interval for the proportion of State College students who smoke.
3. ### statistics

In a random sample of 112 State College students, 41 students reported being current smokers. a) Calculate the 95% confidence interval for the proportion of State College students who smoke.
4. ### Math

Suppose that 40% of all college students smoke cigarettes. A sample of 20 is selected randomly. What is the probability that at most a fourth of the students smoke?
5. ### Math

Suppose that 40% of all college students smoke cigarettes. A sample of 10 is selected randomly. What is the probability tha t a half of the students smoke?
6. ### Statistics

You want to know if there's a difference between the proportions of high school students and college students who read newspapers regularly. out of a random sample of 500 high-school students, 287 say they read newspapers
7. ### Statistics Math

1. What type of car is more popular among college students, American or foreign? One hundred fifty-nine college students were randomly sampled and each was asked which type of car he or she prefers. A computer package was used to
8. ### Statistics

You want to know if there's a difference between the proportions of high school students and college students who read newspapers regularly. out of a random sample of 500 high-school students, 287 say they read newspapers
9. ### Math-Statistics

A marketing research company needs to estimate which of two soft drinks college students prefer. A random sample of n college students produced the following 98% confidence interval for the proportion of college students who
10. ### Statistics

2. A researcher wants to find out how students feel about a proposal to ban smoking on campus. She selected THREE groups of “students who currently smoke”, “students who formerly smoke”, and “students who never smoke”.

More Similar Questions