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1) A coin having probability p of coming up heads is continually flipped until both heads and tails have appeared. find (a) the expected number of flips (b) the probability that the last flip lands heads 2) Ten hunters are waiting for ducks to fly by. when a flock of ducks flies overhead, the hunters fire at the same time, bu

Probablity of telephone customers using a particular service provider

The nation's largest cell phone service provider, with 36 million subscribers out of a total of 148 million cell phone users in the U.S. is XYZ company. If six cell phone users are randomly selected on the street, what is the probability that at least one of the is a XYZ subscriber?

Probability distribution for student survey

100 students in a statistics class were asked if they believed that all tests on the Monday following the football game win over their rival should be postponed automatically. The results were: Strongly agree: 40 Agree: 30 Neutral: 20 Disagree: 10 Strongly disagree: 0 Numeric scale

Probability: failure of cd in random sample of 5

If 10% of all disk drives produced on an assembly line are defective, a. What is the probability that there will be exactly one defect in a random sample of 5 of these? b. What is the probability that there will be no defects in a random sample of 5?


How many different ways can I choose 5 different stocks from a list of 30 stocks? I think I need to use the combination formula. Then based on my answer what is the probability that 3 individuals will select the same 5 stocks?

Leveraging Probability Distributions

On the attach file X school has compiled a large database of survey responses from 288 individuals which contains the following information: (1) Gender (2) Age (3) Department (4) Position (5) Tenure (6) Overall Job Satisfaction (7) Intrinsic Job Satisfaction - Satisfaction with the actual performance of the job (8) Extrins

Determine how many burgers would have to be sold to break even. Determine if these data are normally distributed at a significance level of alpha = 0.05. Simulate the arrival of customers at the pharmacy for the first 20 arrivals. Compute the exponentially smoothed forecast.

1. Funkia Mina is a convenient store located in Goderich and sells a wide variety of supplies. The manager of the store has noticed that several delivery services near Goderich make frequent deliveries. As such, the manager is considering selling burgers at the store. He could buy pre-made burgers and heat them in an oven. The c

Unemployed Workers: Recent Downtrend in Economy

During a recent downtrend in the economy, 30% of the workforce in a medium sized United States town was unemployed, 20% were eligible for food stamps and 10% fell into both categories. If a worker is selected at random in this town, find the probability that he or she a. is unemployed and eligible for food stamps. b. is u

Probability Problems - Defective Fuses

1. A box contains ten fuses of which 3 are defective. Two fuses are selected at random from the box without replacement. What is the probability that exactly one of the fuses selected is defective? 2. A box contains one hundred fuses of which 30 are defective. Ten fuses are selected at random from the box with replacement.

Business Statistics: Mean, Standard Deviations

I could use some help with the following. Could you please explain how you get the answer to the following questions in detail please so I can compare them to mine? I do not understand my book very well and I want to make sure I understand them correctly before I turn them in. Thank you My first question is; The mean start

Probabilities and Expected Value

For exercises 1 and 2, determine whether a probability distribution is given. If it is not described, identify the requirements that are not satisfied. If it is described, find its mean and standard deviation. 1. When manufacturing DVDs for Sony, batches of DVDs are randomly selected and the number of defects x is found fo

Continuous probability distribution - Dental insurance for employees

Shaver Manufacturing, offers dental insurance to its employees. A recent study by the Human Resource Director shows the annual cost per employee per year followed the normal distribution, with a mean of $1280 and a standard deviation of $420. What fraction of the employees cost more than $1500 per year for dental expenses?

Continuous Probability Distributions

A normal population has a mean of 12.2 and a standard deviation of 2.5. How do I compute the z value associated with 14.3? Also, what proportion of the population is between 12.2 and 14.3? Last, what proportion of the population is less than 10.0?

Flipping a coin 10,000 times

A coin tossed 10,000 times. Heads appears 5,100 times. Do you think the coin is fair at a 5% level of significance? At a 1% level of significance?

Limiting distributions

Let Y1 denote the first order statistic of a random sample of size n from a distribution that has pdf f(x)=e^-(x-theta), theta <x< infinity, zero elsewhere. Let Zn=n(Y1- theta). Investigate the limiting distribution of Zn. Answer: Gamma(alpha=1, Beta=1) Please show detail.

Probability calculations using Normal Distribution

According to The American Consumer report of 1990, 44% of males say that they would buy a very expensive car if they won a million-dollar lottery. Suppose we conducted the same survey in 2000 and asked 1000 males the same question. 1) What is the probability that more than 45% of males will say that they would purchase an e

Probability and R.V

1) An elevator starts at the basement with 8 people (not including the elevator operator) and discharges them all by the time it reaches the top floor, number 6. In how many ways could the operator have perceived the people leaving the elevator if all people look alike to him? what if 8 people consisted of 5 men and 3 women and

Busines Statistics: 8 Multiple choice questions on probability

EXHIBIT 4: The student body of a large university consists of 60% female students. A random sample of 8 students is selected. (1) Refer to Exhibit 4. What is the probability that among the students in the sample exactly two are female? a. 0.0896 b. 0.2936 c. 0.0413 d. 0.0007 e. None of the above

Probability, Statistics

Problem: A five-number summary for a box plot includes which of the following? a. Q1, Q2, Q3, Q4, total b. Min, median, max, average, frequency total c. Q1, Q2, Q3, Q4, average d. min, Q1, Q2, Q3, max e. None of the above

Probability & Statistics

Problem: The IQ of adults in a certain large population is normally distributed with mean 100 and standard deviation10. If a person is chosen at random form this group. the probability that the person's IQ is less than 85 or greater than 110 is: a. 0.7745. b. 0.9081. c. 0.2255. d. 0.0919. e. none of the above


1. Here are some interesting (and imaginary) facts about cockroaches: The average number of roaches per home in the United States is 57; s = 12. The average number of packages of roach killer purchased per family per year is 4.2; s = 1.1. The correlation between roaches in the home and roach killer bought is .5. (a) The Clean

Posterior probability

Using the following information about the accuracy of a market research firm: Probability of a favorable study given a favorable market = 0.7 Probability of an unfavorable study given a favorable market = 0.3 Probability of a favorable study given an unfavorable market = 0.05 Probability of an unfavorable study given an un


The following is a payoff table giving profits for various situations: States of Nature Alternatives A B C Alternative 1 120 140 120 Alternative 2 200 100 50 Alternative 3 100 120 180 Do Nothing 0

Probability in dice rolling

1) in successive rolls of a pair of fair dice, what is the probability of getting 2 sevens before 6 even numbers? 2) suppose that an ordinary deck of 52 cards (contain 4 aces) is randomly divided into 4 hands of 13 cards each. p is the probability that each hand has an ace. Ei is the event that the ith hand has exactly one ac


1) an urn contains n white and m black balls. the balls are withdrawn one at a time until only those of the same color are left. show that with probability n/(n+m) they are all white. 2) an urn contains 5 white and 10 black balls. a fair die is rolled and that number of balls is randomly chose from the urn. what is the probabil

Multiple questions on probability and distributions

(24) A study by the National Park Service indicates that 60% of the vacationers going to the Rocky Mountain region visit the Yellowstone Park, 30% visit the Tetons, and 15% visit both. What is the probability that a vacationer to Yellowstone will visit the Tetons? a. 25% b. 50% c. 45% d. 90% e. None of the ab

Using Probability to Estimate IQ

The IQ of children in a certain population is normally distributed with mean 100 and standard deviation 10. If a child is randomly chosen from this group, the probability that the child's IQ is less than 85 or greater than 110 is? a. .0919 b. .2255 c. .9081 d. .7745