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5 Statistics Problems: Normal Probability, Samples, and Confidence Intervals

1- Surveying all drug stores in the Boston area, it was found that the average cost of a chocolate mint frappe is $30.50. The cost of a mint frappe population is normally distributed, with a standard deviation of $0.50. If I select a drug store in the Boston area randomly, what is the probability that the cost of is chocolate mi

Solving puzzles; inspecting computer shipments

A multi choice exam offers 4 choices for each question. Jason guesses the answers, so he has a probability 1/4 of getting any one question correct. 1) What is the expected number of right answers Jason will get if the test has 20 questions? Data on number of puzzles solved by a person are as follows: Puzzles solved:


A TV show, DOG and CAT, recently had a share of 20, meaning that among the TV sets in use, 20% were tuned to that show. Assume that an advertiser wants to verify that 20% share value by conducting its own survey, and a pilot survey begins with 9 households having TV sets in use at the time of a GOD and CAT broadcast: - Find


In a region, 20% of the population has brown eyes. If 15 people are randomly selected, find the probability that at least 13 of them have brown eyes. Is it unusual to randomly select 15 people and find that at least 13 of them have brown eyes? - The probability at least 13 of 15 have brown eyes = ____ (three decimal places


An insurance company charges a 21 year old male a premium of $250 for a one year $100,000 life insurance policy. A 21 year old male has a 0.9985 probability of living for a year. From the perspective of a 21 year old male (or his estate), what are the values of the two different outcomes The value if he lives is $_______ T


Based on data from a car bumper sticker study, when a car is randomly selected, the number of bumber stickers and corresponding probabilities are shown below. 0 (0.794) 1 (0.099) 2 (0.041) 3 (0.015) 4 (0.014) 5 (0.012) 6 (0.008) 7 (0.006) 8 (0.006) 9 (0.005) Does the given info describe a probability distribution

Poisson Distribution

An insurance company charges $226 for a $50,000 life insurance policy for a 50 year-old female. The probability that such a female survives the year is 0.9969. Assume that the company sells 750 such policies to 50 year-old females, and it collects $169,5000 in policy payments. The company will make a profit if fewer than four

Binomial Probability Distribution

Determine wheter the given procedures results in a binominal distribution. If it is not binomial, identify the requirements that are not satisfied. Treating 20 men with a special shampoo and asking if they experience any burning  __ NO, because there are more than two possible outcomes and the trails are not independent.

Probability Distribution

Determine whether the distribution is a discrete probability distribution: x P(x) 0 .25 1 .30 2 -.10 3 .30 4 .25 Is the probability distribution a discrete distribution?

Normally distributed output: What is true about the mean of the process?

A process when in control produces a normally distributed output with a mean of 200 and a range of 20. Ten samples of 20 each yield the following means and ranges. Sample 1 2 3 4 5 6 7 8 9 10 X-Bar 200 202 201 204 203 203 201 201 202 201 Range 19.0 20.0 20.2 20.7 19.0 21.1 19.0 20.1 20.3 21.7 Which of the following is mos

Probability, mean, variance, standard deviation,

Please solve in Excel only. 1. The Penguin Company employs 400 men and 100 women. Of the male employees, 280 work in the plant, 40 are in the office, and 80 are field salesmen. The female employees are distributed as follows: 20 to the plant, 50 to the office, and 30 to the sales. If the CEO, Stephanie, randomly selects an

Statistics: Probability distribution, random variable, Poisson distribution

1. Compute the following and show your steps. 3! ÷ (0!*3!) 2. Three members of a club will be selected to serve as officers. The first person selected will be president, the second person will be vice-president and the third will be secretary/treasurer. How many ways can these officers be selected if there are 30 club memb


If a couple were planning to have three children, the sample space summarizing the gender outcomes would be: bbb,bbg,bgb,bgg,gbb,gbg,ggb,ggg: 1. Construct a similar sample space for the possible gender outcomes (using b for boy a g for girl) of two children? 2. Assuming that the outcomes listed in part 1 were equally likel

Probability of Winning a Lottery

What is the probability of winning a lottery with the following rule. Select five winning numbers from 1,2,.....44 (In an order and no repeats) P (winning) = _____ (integer or simple fraction)


Use the given results from a test to answer the following question: Among 143 subjects with positive test results, there are 29 false positive; Among 155 negative results, there are 4 false negative results. If one of the test subjects is randomly selected, find the probability that the subject tested negative or did no


A research center poll showed 80% of people believe that it is morally wrong to not report all income on tax returns. What is the probability that someone does not have this belief? The probability that someone does not believe that it is morally wrong to not report all income on tax returns is ____ (integer or decimal)

Probabilities of number of fish caught at a particular location on a river

At a particular location on a river the number of fish caught per man-hour of fishing effort has a Poisson distribution with ?= 1.3 fish per man hour. Find the following probabilities: a. That four fish will be caught by one man fishing 2 hours. b. That six fish will be caught by three men fishing 20 minutes each.

Poisson distribution: Manuscript pages typing errors

In a lengthy manuscript, it is found that only 2/3 of the pages contain no typing errors. Assume that the number of errors per page has a Poisson distribution. a. Find the expected number of errors per page? b. What percentage of pages has exactly one error?

Known mean population and an unknown variance

A normal population has a known mean 50 and unknown variance. a) A random sample of n=16 is selected from this population and the sample results are x-bar = 52 and s= 8. How unusual are these results? Explain. b) A random sample of n=30 is selected from this population and the sample results are x-bar = 52 and s=8. How unu

Discrete Probabilty Distributions for Lottery Payouts

The payouts of the lottery and their corresponding odds and probabilities of occurrence are shown below. The price of a ticket is $1.00. Find the mean and standard deviation. Hint: don't forget to include the cost of the ticket and its corresponding probability. Divisions Payout Odds

Microsoft, Apple and Google, descriptive, correlation matrix, plot, variables

Date Google Close Microsoft Close Apple Close 31/12/2009 619.98 30.34 210.73 30/12/2009 622.73 30.82 211.64 29/12/2009 619.4 31.24 209.1 28/12/2009 622.87 31.02 211.61 24/12/2009 618.48 30.86 209.04 23/12/2009 611.68 30.78 202.1 22/12/2009 601.12 30.68 200.36 21/12/2009 598.68 30.38 198.23 18/12/2009 596.42 30.22 195.43

Statistics Probability 3 problems

1. If we know that the length of time it takes a college student to find a parking spot in the library parking lot follows a normal distribution with a mean of 3.5 minutes and a standard deviation of 1 minute, find the probability that a randomly selected college student will find a parking spot in the library parking lot in les

Probability Distribution 3 problems

1. The following table contains the probability distribution for X = the number of traffic accidents reported in a day in Corvallis, Oregon. The probability of at least 3 accidents is ________. a. 0.25 b. 0.15 c. 0.75 d. 0.20 2. A certain type of new business succeeds 60% of the time. Suppos

Binomial & Normal Probabilities..

1. CNBA basketball player Steve Swoopes scores on 85% of his foul shots. If he gets eight foul shots during a game, what is the probability that he will score on exactly seven of them? 2. A manufacturing company uses a binomial distribution to predict the number of defective units among its products. What is a "success" in t