When parking a car in a downtown parking lot, drivers pay according to the number of hours or parts thereof. The probability distribution of the number of hours cars are parked has been estimated as follows: x 1 2 3 4 5 6 7 8 P(x) 0.24 0.18 0.13 0.1 0.07 0.04 0.04 0.2 Find the mean an
Using historical records, the personnel manager of a plant has determined the probability distribution of X, the number of employees absent per day. It is: x 0 1 2 3 4 5 6 7 P(x) 0.005 0.025 0.31 0.34 0.22 0.08 0.019 0.001 a. Find the following probabilities: P(2 ≤ X ≤
A gambler believes that a strategy called "doubling up" is an effective way to gamble. The method requires the gambler to double the stake after each loss. Thus, if the initial bet is $1, after losing he will double the bet until he wins. After a win he resorts back to a $1 bet. The result is that he will net $1 for every wi
Suzy and Fran toss a coin over cab fare. The probability that Suzy will pay five days in a row is 0.03125. True or False?
If R and S are independent events with P(R) = 0.30 and P(S) = 0.50, then P(R or S) = 0.65. True or false?
If P(A)=0.84, P(B)=0.76 and P(A or B)=0.90, then what is P(A and B)?
Long-term history has shown that 65% of all elected offices in a rural county have been won by Republican candidates. This year there are 5 offices up for public election in the county Let r be the number of public offices won by Republicans. a) Find P(r) for r=0,1,2,3,4, and 5 b) Make a histogram for the r probability d
1. A May, 2004 news report indicated that George Bush 74% overall approval rating among Republicans. 26% of all others disapprove. Assume that 45 percent of registered voters are Republican. If you select a registered voter at random and the voter approves of the President's performance, what are the chances that the voter is a
Many vehicles used in space travel are constructed with redundant systems to protect the flight crew and their equipment. In other words, backup systems are included with many vehicle components so that if one or more systems fail, backup systems will assure the safe operation of the given component and thus the entire vehicle.
Suppose it is known that the distribution purchase amounts by customers entering a popular retail store is approximately normal with mean $25 and standard deviation $8. a. What is the probability that a randomly selected customer spends less than $35 at the store? b. What is the probability that a randomly selected custom
Consider the following continuously operational job shop. Inter arrival times of jobs are described as follows: Time between arrivals (hrs) probability 0 0.23 1 0.37 2 0.28
In the 107th Congress, the Senate consists of 13 women and 87 men. If a lobbyist for the tobacco industry randomly selects three different senators, what is the probability that they are all women? An article in USA Today stated that "Internal surveys paid for by directory assistance providers show that even the most accurate
1. For a sample selected from a population with a mean of µ=50 and a standard deviation of σ = 10: a. What is the expected value of M and the standard error of M for a sample of n=4 scores? b. What is the expected value of M and the standard error of M for a sample of n = 25 scores? 2. A population has a mean of µ
An unprepared student takes a three-question, true/false quiz in which he guesses the answers to all three questions, so each answer is equally likely to be correct or wrong. a)(4)The student gets three answers wrong. b)(4)The student gets exactly two answers correct. c)(4)The student gets only the first answer correct.
Suppose a certain test detects cancer among people ... [See the attached question File.]
A manufacturer of hard drives knows that the average life of a hard drive is five years with a standard deviation of one year. If he only wants to warranty the drive for three years, what proportion of hard drives should he expect to replace? Assume the normal distribution.
If a= 0.05, what is the probability of making a Type I error? a.0 b.1/20 c. 19/20 d. 20/20
Please help with the following probability problem. According to the American Federation of Teachers, the average salary of 1998 college graduates with a degree in accounting was $33,702 (USA Today, June 18, 1999). Assume that the distribution of current salaries of recent graduates with a degree in accounting is skewed to t
Two-liter plastic bottles used for bottling cola are shipped in lots of 100. Suppose the lots are 5 percent defective. Some bottles leak, some are too small, and so forth. a. In the sample of 100, how many of the bottles would you expect to be defective? What is the standard deviation? b. Tell why this situation meets the
The Food King Chain employs more than 3,000 people. The worker's ages are approximately normally distributed, with a mean of 31 years and a standard deviation of 4.3 years. The company is thinking of introducing a health care package, and its insurance company wants to sample 31 workers before quoting a price. Calculate the prob
The heights of women at a large university are approximately bell-shaped, with a mean of 65 inches and standard deviation of 2.5 inches. Use this information to answer the following questions: a) What is the probability that a randomly selected woman from this university is 67.5 inches or taller? b) What is the probability
A person claims to have ESP (extrasensory perception). A coin is tossed 16 times, and each time the person is asked to predict in advance whether the coin will land heads or tails. The person predicts correctly 75% of the time (i.e., on 12 tosses). What is the probability of being correct 12 or more times by pure guessing?
Suppose that students' commuting time at CSN, represented by the variable X, has mean= 29 minutes and standard deviation = 9 minutes. There are 6000 students at CSN and we are about to take a random sample of 40 students. a) Can we know in advance what the mean commuting time for the students in the sample will be? b) Calcu
The manager of a car wash receives pricing schedule (shown below) from the vendor who supplies soap- and a promise of a 25% shorter lead time for deliveries. Currently, lead time is 4 days. Annual usage of soap is 4500 gallons. The car wash is open 360 days a year. Ordering Costs is $ 30 per order and annual holding costs are $
Determine the value of c that makes the function f(x,y) = c(x+y) a joint probability density function over the range: x greater than 0 and less than 3 and x less than y less than x+2 a) P(X<1, Y<2) b) P(1<X<2) c) P(Y>1) d) P(X<2, Y<2) e) E(X) f) V(X) g) Marginal probability distribution of X h) Conditional probabilit
Expectation and variance of a random variable Let X be a random variable with the following probability distribution: ... [See the attached Question File.]
The time between surface finish problems in a galvanizing process is exponentially distributed with a mean a 40 hours. A single plant operates three galvanizing lines that are assumed to operate independently. a) What is the probability that none of the lines experience a surface finish problems in 40 hours of operations? b
Question 1. An audit conducted by the St. Aleanis Hospital has determined that 15% of all patient bills contain an error of one form or another. After spending considerable effort to improve the hospital's billing process, the administrators are convinced that things have improved. They believe that the new error rate is somewhe
Amount of soft drink distributed into a cup has a mean of 7.6 oz and standard deviation of 0.4 oz. using what is given a) Estimate the probability that machine will overflow an 8oz cup b) Estimate the probability that it will not over flow 8 oz cup c) The machine has been loaded with 850 cups. how many of these do you expect
Incubated time for black chicks is distributed with a mean of 21days and standard deviation of 1 day.using what is given, If 1000 eggs are being incubated how many chicks do we expect to hatch a) in 19-23 days, in 20 to 22 dayd b) in 21 days or fewer d) in 18 to 24 days assuming all eggs hatched. This is what is given:u-3(me