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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

Popularity of Presidential Candidates

Nine presidential candidates are ranked in popularity according to a recent poll and the top three in order are announced: George (1); Thomas (2); and James (3). If three candidates were picked at random, what is the probability of picking those three and in that order?

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.

probability of selecting gloves randomly

A box of 9 gloves contains two left handed gloves and seven right handed gloves. a: If two gloves are randomly selected from the box, without replacement, what is the probability that both gloves will be right handed? b: If two gloves are randomly selected from the box without replacement, what is the probability that ther

Inventory Control - Monte Carlo Simulation

Good Day, Could you please assist with the attached question. Regards Q3 - Inventory Control: Monte Carlo Simulation A bookstore wishes to carry a certain book in stock. Demand is probabilistic and replenishment of stock takes two days (i.e. if th

Elements of Sample Space

A) Toss a coin 4 time or toss 4 coins once. List the elements of the sample space of the experiment. b) how many 4-digit numbers can be formed from the digits if - each digit can be used only once - the digits may be repeated?

Average Profit and Basic Probability

1. A ski resort profits $1,200,000 during a good winter with lots of snow. The resort has a loss of $450,000 otherwise. The resort's historical climate data suggests that the probability of a good winter with lots of snow during any given year is 60%. What is the expected profit for the ski resort? Show significant work to justi

Probability and Binomial Distribution

An investment opportunity has several outcomes as shown in the table. The amounts are in dollars. The probability for each amount is given on the second line of the table. Please answer the questions posted in the attachment.

Is lack of sleep causing traffic fatalities?

Please show work. 45. Is lack of sleep causing traffic fatalities? A study conducted under the auspices of the National Highway Traffic Safety Administration found that the average number of fatal crashes caused by drowsy drivers each year was 1550 (Business Week, January 26, 2004). Assume the annual number of fatal crashes

Normal Distribution and Final Examination Probability

Please show work. 23. The time needed to complete a final examination in a particular college course is normally distributed with a mean of 80 minutes and a standard deviation of 10 minutes. Answer the following questions. a. What is the probability of completing the exam in one hour or less? b. What is the probabil

Normal probability calculation ..

Please show work. 5. The driving distance for the top 100 golfers on the PGA tour is between 284.7 and 310.6 yards (Golfweek, March 29, 2003). Assume that the driving distance for these golfers is uniformly distributed over this interval. a. Give a mathematical expression for the probability density function of driving di

A metropolitan school system consists of three school districts

A metropolitan school system consists of three school districts-norths, south, central. The north district contains 25% of all students, the south district contains 40%, and the central district contains 35%. A minimum-competency test was given to all students; 10 % of the north district students failed, 15% of the south dis

Panic Attacks and Exponential Distribution

It has been demonstrated that the time until a panic attack is experienced by students during a statistics exam can be modeled as an exponential distribution with λ equal to .037^-1 minutes. a) What is the probability that a student taking a statistics exam will experience his/her first panic attack within the first 10 m

Interval of Pulses in a Communications Channel

The number of pulses a communications channel receives per second can be modeled with a Poisson distribution with a rate parameter of 2.0. a. What is the probability the channel receives at least 2 pulses in a one second interval? b. What is the probability that no pulses are received in a 5 second interval?

Mean of Distribution

The probability distribution for the possible results of an experiment is given, Determine the mean of the distribution. X P(X) 1 0.100 3 0.300 5 0.425 7 0.175 Round mean to nearest 10th

Probability - Exponential Distribution

The time to failure of a supercomputer has an exponential distribution with a median of four hours. Find the probability that the computer runs without a failure for at least six hours.

Joint PDFs

Respond to OTA: Basically the first equation is the joint pdf of a sample maximum and minimum - if I am not wrong - it is just the formula. The problem is finding the joint pdf from the sample size drawn from the pdf (2nd equation given between the bolded text ). So basically A(1) and A(n)corresponds only to the 2nd equation

Arrangements, Combinations, Permutations and Probabilities

1. You have 3 suits, 7 shirts, 10 ties--how many arrangements--answer and equation. 2. 20 cars, 5 defective, sample of 4 selected, what is probability one of the 4 is defective--answer and equation. 3. You have 4 identical gift cards-to give among 8 customers --how many arrangements are there--answer and equation. 4. Yo