Assignment Solutions
A western city has 18 police officers eligible for promotion. Eleven of the 18 are Hispanic. Suppose only five of the police officers are chosen for promotion and that one…
Random samples of households were selected from each of three regions in a large metropolitan area. The number of households selected from each region and the corresponding mean household incomes…
Earnings by gender According to the 2005 American Community Survey taken by the U.S. Bureau of the Census, the median earnings in the past 12 months was \$32,168 for females…
In a history class there are 25 freshman, 21 sophomores, and 18 juniors. If the freshman averaged 81 on an examination, the sophomores averaged 84, and the juniors averaged 72,…
The first assignment in a statistical computing class involves running a short program. If past experience indicates that 40% of all students will make no programming errors, compute the (approximate)…
False-positives in testing for HIV. A rapid test for the presence in the blood of antibodies to HIV, the virus that causes AIDS, gives a positive result with probability about…
A pharmacist receives a shipment of 23 bottles of a drug and has 3 of the bottles tested. If 6 of the 23 bottles are contaminated, what is the probability…
In the United States, 44% of the population has type O blood. Suppose a random sample of 12 persons is taken. Find the probability that at most 6 of the…
The amount of time that a union stays on strike is judged to follow an exponential distribution with a mean of 10 days. a. Find the probability that a strike…
