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Statistics and Probability in Computing

1) When sending data over the internet there is a certain probability that a message will be corrupted. One way to improve the reliability of getting messages through is to use a Hamming Code. This involves sending extra data that can be used to check the main message. For example a 7 bit Hamming Code contains 4 bits of message

Develop an OC curve for this sampling plan

This is a practice question for my statistic final, if I can get this explained to me the rest will be a piece of cake. I think I need some confidence. At the beginning of each football season Team Sports, the local sporting goods store, purchases 5,000 footballs. A sample of 25 balls is selected, and they are inflated, test


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

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?

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 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: 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

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

Calculating Probability of a Value Being in a Certain Range

A normal distribution has a mean of 50 and a standard deviation of 4. a. Compute the probability of a value between 44.0 and 55.0. b. Compute the probability of a value greater than 55.0. c. Compute the probability of a value between 52.0 and 55.0.

Probability of Key Selection

A woman has n keys, of which one will open her door. (a) if she tries the keys at random, discarding those that do not work, what is the probability that she will open the door one her kth try? (b) what if she does not discard previously tried keys?

Probability-Poker Hands

If it is assumed that all (52 5) poker hands are equally likely, what is the probability of being dealt (a) one pair (a,a,b,c,d) , (b) two pairs (a,a,b,b,c) (c) three of a kind (a,a,a,b,c).

Uniform Probability Distribution - Words Per Minute

A company requires its secretarial employees to demonstrate his/her ability to type more than 45 words per minute in a typing test. The incompetent employees will be terminated. Lucy's typing rate is uniformly distributed between 30 and 50 words per minute. 1. What is the probability that she can type 45 to 50 words per mi