Asked Jan 17, 2020

Drug Tests There is a 3.9% rate of positive drug test results among workers in the United States (based on data from Quest Diagnostics). Assuming that this statistic is based on a sample of size 2000, construct a 95% confidence interval estimate of the percentage of positive drug test results. Write a brief statement that interprets the confidence interval.


Expert Answer

Step 1

The 95% confidence interval for the percentage of positive drug test result is obtained below:

The critical value is obtained below.

 From the given information, the best estimates of the population proportion is 3.9% that is 0.039, the sample size is 2,000 and the confidence level is 0.95 and then from the standard normal table the critical value is 1.96.

The margin of error is obtained below:

Statistics homework question answer, step 1, image 1
Step 2

The 95% confidence interval for the proportion...

Statistics homework question answer, step 2, image 1

Want to see the full answer?

See Solution

Check out a sample Q&A here.

Want to see this answer and more?

Solutions are written by subject experts who are available 24/7. Questions are typically answered within 1 hour.*

See Solution
*Response times may vary by subject and question.
Tagged in



Hypothesis Testing

Related Statistics Q&A

Find answers to questions asked by student like you
Show more Q&A

Q: Lognormal Distribution The following are the values of net worth (in thousands of dollars) of recent...

A: The values of net worth are,237592, 16068, 153250, 11712, 7304, 6037, 4483, 4367, 2658, 1361 and 311


Q: What is the binomial distribution?

A: The binomial probability distribution is a discrete probability distribution in which the outcomes a...


Q: Insomnia Treatment A clinical trial was conducted to test the effectiveness of the drug zopiclone fo...

A: One sample t test:Here, n is 16, x-bar is 98.9 and s is 42.3Since population standard deviation is n...


Q: Standard Error of Estimate A random sample of 118 different female statistics students is obtained a...

A: The data show the statistics of 118 different female students paired weights (weight in kg, weight i...


Q: Bone Density Test. In Exercises 1–4, assume that scores on a bone mineral density test are normally ...

A: The probability of the bone mineral density test score z between 0.87 and 1.78 is obtained by findin...


Q: How many 5 letter codes are possible from the first 7 letters of the alphabet? a.) letters can be re...

A: Excel is used to obtain the line and bar graph for years of education and years of experience, respe...


Q: Interpreting Normal Quantite Plots. In Exercises 5–8, examine the normal quantite plot and determine...

A: In the normal quantile plot, the points represent the tornadoes traveled distances. Also, the points...


Q: In Exercises 6–10, assume that women have diastolic blood pressure measures that are normally distri...

A: The random variable x represents the diastolic blood pressure of women.The 90th percentile for the d...


Q: Checking Requirements Common tests such as the SAT, ACT, Law School Admission test (LSAT), and Medic...

A: Solution: We are given that there are 100 multiple choice question with five possible answers and on...