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Public Safety and Speeding Tickets: Probabilities

The department of public safety surveyed drivers to see how many of them had received a speeding ticket for driving at least 20 MPH above the posted speed limit. It was reported that 25% of the licensed drivers in a certain county had received speeding tickets for driving 20 MPH above the posted speed limit. In June, 30 licensed


The human resource director of Sunshine Corporation uses a paper-pencil test that measures work habits to help decide whom to hire. From her past research with the company, she has found the correlation-for those who are hired-between the work-habits inventory and a job performance scale after one year to be +.80. She decides to

Two questions involving order statistics

1. Ten observations of X are 67 6 7 35 78 28 74 5 9 37 a) Find the order statistics b) Find the median and 80th percentile of the sample c) Determine the first and third quartiles of the sample 2. Let Y1<Y2<Y3<Y4<Y5 be the order statistics of 5 independent observations of an exponential distribution with

Determine population, sample and variable of interest

A random sample of 1001 University of California faculty members taken in December 1995 was asked, "Do you favor or oppose using race, religion, sex, color, ethnicity or national origin as a criterion for admission to the University of California?" (Roper Center, 1996). 52% responded "favor". a.What is the population for this

1. A recent survey of 1000 adults shows that 58% believe airplanes to be the safest mode of travel. Construct a 99% confidence interval for the proportion of adults who think airplanes are the safest mode of transportation. 2. An aptitude test has a mean score of 80 and a standard deviation of 5. The population of scor

A coin is flipped 50 times - probability

1. A coin is flipped 50 times. a)Calculate the probability that exactly 10 coin flips are heads. b)Calculate the probability that 10 coin flips or less are heads. 2.The expected number of work accidents in a year is 11.5. a) Calculate the probability that there are exactly 10 accidents in a randomly selected year.

Electronics specializes in manufacturing electronic components

Please check the attachment. 1) Todays electronics specializes in manufacturing modern electronic components. It also builds the equipment that produces the components. Phyllis Weinberger, who is responsible for advising the president of Today's Electronics on electronics manufacturing equipment, has developed the following tab

Statistics questions

Can you help me with statistic questions? *The standard deviation of a point estimator is called the _______? (A) standard error (B) sample mean (C) population standard deviation (D) probability distribution *The t-distribution can be used with small samples for establishing confidence intervals for the population mean, pr

Completion Time of Projects

A project was planned using PERT with three time estimates. The expected completion time of the project was determined to be 40 weeks. The variance of the critical path is 9. What is the probability that the project will be finished in 46 weeks or less? A. 2% B. 73% C. 98% D. impossible to determine with this informati

Probability in 200 Dice Rolls

Find the probability that in 200 tosses of a fair six-sided die, a five will be obtained at most 40 times. Please provide the detail of how to calculate.

The difference between a discrete and a continuous random variable.

1) Explain the difference between a discrete and a continuous random variable. Give two examples of each type of random variable. 2) Determine whether each of the distributions given below represents a probability distribution. Justify your answer. a) x 1 2 3 4 P (x) 1/8 1/8 3/8 1/8 b) x 3 6 8 P (x) 0.2

Probability that Mean Daily Precipitation will be 0.095+

According to records, the amount of precipitation in a certain city on a November day has a mean of 0.10 inches, with a standard deviation of 0.06 inches. What is the probability that the mean daily precipitation will be 0.095 inches or more for a random sample of 40 November days (taken over many years)? Carry your interm

Binomial probability

The unemployment rate in a city is 13%. Find the probability that more than 2 out of 10 people from this city sampled at random are unemployed. Round your answer to four decimal places.

Probability of Prophecy Fulfilled

Based on the below account of prophecy and fulfillment how do I write out the answer based on the formula to solve the equation. I guess for statistics sake we could say that he could have ridden in on a camel, horse, or donkey. How do I go about doing this? Thanks for your help? SO would the probability be .50 a yes he wou

Catalyst Data Corporate Officer

According to Catalyst, a New York based women's advocacy and research group, 12% of all corporate officer's at the 500 largest U.S. corporations in 1999 were women, compared to 8% in 1995. a.) According to catalyst data, in sample of 1,000 corporate officer's at the 500 largest U.S. firms, how many would you expect to be wo

Fluctuation in the prices of precious metals such as gold have been empirically shown to be well approximated by a normal distribution when observed over short interval of time. What is the probability that the client's gold will be sold the next day?

Fluctuation in the prices of precious metals such as gold have been empirically shown to be well approximated by a normal distribution when observed over short interval of time. In May 1995, the daily price of gold (1 troy ounce) was believed to have a mean of $383 and a standard deviation of $12. A broker, working under these a

There is a 20% probability of a rain tomorrow means that ...

WHICH ANSWER IS RIGHT 1, 2, OR 3 AND WHY? There is a 20% probability of a rain tomorrow means that: 1. Tomorrow it will be raining during 0.2 of the day, and the rest of the day it will be clear; 2. Out of the next 5 days, one day it will be raining ; 3. According to the records, if a weather like one we have today occu

American Intellectual Union: Employee Job Satisfaction Report

Compose an email to the head of the American Intellectual Union which discusses the following: Begin your email to AIU by first providing an overview of the database, i.e. a story. Be sure to include information about how you would use the concept of probabilities to apply to profiles for hiring more satisfied individual

Wages in Construction Industry

Wages in the construction industry average $11.90 per hour with a standard deviation of $1.40. What percent of workers make less than $10.50 per hour (z = -1.00)? 2. The probability of employees taking the time to fill out a survey at Comptex is 17%. There are 5 people in the department managed by Alice. What is

Lognormal Distribution & Probability

1. If X, Y are lognormal distribution, what the distribution of X/Y? 2. what is the probability of getting 40 or less heads in 100 coin tosses. What distribution is this. With what other distribution can you approximate this. What is the final probability. 3. Which is greater exp((a+b)/2) or (exp(a)+exp(b))/2 4. what

Let X be a random variable representing the sum of trials.

Let X be a random variable representing the sum of trials. Then X is a binomial random variable if all of the following are satisfied except a. no two trials can have the same outcome b. p, the probability of "success" on any trial is the same for all trials c. each trial has exactly two possible outcome

Probability of Smokers

For questions 1 through 3 use the table below. The table shows the number of smokers and nonsmokers by gender among 220 people. Assume one person is chosen at random from the 220. Smokers Nonsmokers Totals Male 40 60 100 Female 40 80 120 Totals 80 140 220 1. If a smoker is chose

Tree Diagrams for Conditional Probabilities

Please see attached file for full problem description. Tree diagrams for conditional probabilities A course in statistics is one of the most difficult at the local university. Because of this, for the past decade the university has arranged for teaching assistants to hold frequent discussion sessions as part of the course.