50% of first marriages and 67% of second marriages end in divorce, so says Jennifer Baker of the Forest Institute of professional psychology in Springfield, Missouri. In a random sample of 200 second-marriages, What is the expected number that will end in divorce?

In an article that appears on a website,† Carlton Gunn, a public defender in Seattle, Washington, wrote about how he uses statistics in his work as an attorney. He states the following. I personally have used statistics in trying to challenge the reliability of drug testing results. Suppose the chance of a mistake in the taking and processing of a urine sample for a drug test is just 1 in 100. And your client has a "dirty" (i.e., positive) test result. Only a 1 in 100 chance that it could be wrong? Not necessarily. If the vast majority of all tests given—say 99 in 100—are truly clean, then you get one false dirty and one true dirty in every 100 tests, so that half of the dirty tests are false. Define the following events as given below. TD = event that the test result is dirty TC = event that the test result is clean D = event that the person tested is actually dirty C = event that the person tested is actually clean (a) Using the information in the quote, compute the following…

A political scientist claims that 38% of first-year college students characterize themselves as being “moderate” or “middle of the road” as far as their political affiliation is concerned.   Believing this claimed value is too high, you survey a random sample of 400 first-year college students and find that 120 characterize themselves as being “moderate” or “middle of the road.”    Based on this information, what will the test statistic be? Choose the answer below that is closest to what you calculate, and try not to do a lot of rounding until you get to the very end of your calculations.   1. -0.3 2. -1.2 3. -2.6 4. -3.3 5. None of the other answer options are correct because the test statistic should be positive, not negative.

7. According to a college survey, 22% of all students work full time. In a survey of 14 students, what is the probability that no more than 2 of them work full time?

10. A sample of cars was studied. In the sample, 26 white cars were observed, 23 black, 19 grey and 13 silver. What is the probability a car in the study was black?

The 2015 National Vital Statistics Report provides information on how the nearly four million live births that occurred in 2014 broke down by birth order. Choose at random a baby born in the United States in 2014. Baby's birth order Probability mean = 1 2 0.391 0.319 The few babies who were 9th or more in birth order are included in the "8" birth order group. In 2014, 39.1% of the nearly 4 million live births in the United States were to first-time mothers. 3 5 6 7 4 0.168 0.072 0.028 0.012 0.005 standard deviation = What are the properties of the sampling distribution of the proportion of births to first-time mothers in random samples of 500 births from 2014? (Enter your answer for the mean rounded to three decimal place and your answer for the standard deviation rounded to four decimal places.) 8 0.005

Based on historical data, your manager believes that 31% of the company's orders come from first-time customers. A random sample of 119 orders will be used to estimate the proportion of first-time-customers. What is the probability that the sample proportion is between 0.24 and 0.37?

According to Harper's Index, 60% of all federal inmates are serving time for drug dealing. A random sample of 15 federal inmates is selected. (c) What is the expected number of inmates serving time for drug dealing?

Advertisers contract with Internet service providers and search engines to place ads on websites. They pay a fee based on the number of potential customers who click on their ad. Unfortunately, click fraud—the practice of someone clicking on an ad solely for the purpose of driving up advertising revenue—has become a problem. According to BusinessWeek,  42% of advertisers claim they have been a victim of click fraud. Suppose a simple random sample of  220 advertisers will be taken to learn more about how they are affected by this practice. Use z-table. a. What is the probability that the sample proportion will be within +/- 0.05 of the population proportion experiencing click fraud? (to 4 decimals) b. What is the probability that the sample proportion will be greater than 0.45 ?(to 4 decimals)

Consider the host/seater job in a full-service restaurant. Suppose that it takes an average of 2.5 minutes to greet a group of customers, check their reservation, and seat them. The expected number of new groups arriving during each hour on a particular day is given below. Time period Noon-1 p.m. 1-2 p.m. 2-3 p.m. 3-4 p.m. 4-5 p.m. 5-6 p.m. 6-7 p.m. 7-8 p.m. 8-9 p.m. 9-10 p.m. 10-11 p.m. 11 p.m. -Midnight No of new groups 20 60 20 8 14 14 40 30 50 40 30 14 a. Determine the number of hosts/seaters required during each hour. Round up if the number has a decimal. (Hint: You don't need more than three hosts/seaters for any hour.)