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Lottery Tickets Probability

If ten lottery tickets are sold and you and your friend each bought one, what is the probability your friend will get first prize and you will get second? What about the probability you will get first prize and she will get second?


A cola-dispensing machine is set to dispense 9.00 ounces of cola per cup, with a standard deviation of 1.00 ounces. The manufacturer of the machine would like to set the control limit in such a way that for samples of 36,5 percent of the sample means will be greater than the upper control limits, and 5 percent of the sample mean

Measures of central tendency-the mean, the median, and the mode

Each of the three measures of central tendency-the mean, the median, and the mode-are more appropriate for certain populations than others. For each type of measure, I need two additional examples of populations where it would be the most appropriate indication of central tendency.

A Discussion On Mutual Exclusivity

The events X and Y are mutually exclusive. Suppose P(X) = .05 and P(Y) =.02. What is the probability of either X or Y occurring? What is the probability that neither X nor Y will happen?


The probability -------------------------------------------------------------------------------- 1) A very rich investor has a small amount of spare cash which she wishes to invest. She has four options to choose from. She thinks company 1 has a 43% chance of giving her a return of $327, otherwise she believes it will lose he


Given a worn machine that creates defects at the average rate of 5 units per hour, what 's the probability of no defects occurring in any specific hour? What's the probability of 8 or more defects in any hour?

Window Frames and Defects

I need some help answering this question: A manufacturer of window frames knows from long experience that 5% of the production will have some type of minor defect that will require an adjustment. What is the probability that in a sample of 20 window frames: A. None will need adjustment? B. At least one will need adjustment?

Probabilty Question

A study by the national park services revealed that 50% of vacationers going to the Rocky Mountain region visit Yellowstone Park, 40% visit the Tetons, and 35% visit both. A. What is the probability of vacationer will visit at least one of these attractions? B. What is the probability .35 called? C. Are the events mutally e

In a certain town 63% of the houses have smoke detectors.

In a certain town 63% of the houses have smoke detectors. The fire brigade estimates that people die 24% of the time when the fire is in a house without a smoke detector, but only 13% of the time when there is a smoke detector. In addition 31% of callouts are false alarms that do not involve a fire. What is the probability that

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

Statistics Problem

Suppose that female heights are normally distributed with mean 66 inches and standard deviation 2.5 inches. What is the probability of a female height being less than 61 inches? More that 61 inches? Four different classmates answer these in order with some explanation, please. Show the solutions as well as the answer to ea


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