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Standard deviation and probabilities.

1)Assume x is normally distributed with mean u=15 and standard deviation 0=3. Use the approximate areas beneath the normal curve, as discussed in this section, to answer the following questions. Find p(x<_9) 2)Your high school graduating class had 564 members. Thirty-three percent of these are expected to attend college. The

Simple random sample of overtime hours

Employees in a large manufacturing plant worked an average of 62.0 hours of overtime last year, with a standard deviation of 15.0 hours. For a simple random sample of n=36 employees and x=the number of overtime hours worked last year, determine the z-score corresponding to each of the following sample means:a)x=55.0 hours b)x=

Binomial Probability: find probabilities.

5.A marketing firm wants to target people who eat breakfast by sending out a new product. According to recent statistics three in four people eat breakfast. If the marketer sends out samples to 10 people selected at random, Find the probability using the binomial probability distribution formula. (Show all work) a. Exactly

Statistics & Probability : Sampling

1. On a national standardized test with a normal distribution of scores, a mean of 50, and a standard deviation of 3.2, a student's score is 1.2 standard deviations above the mean. What is the students score? 2. A national achievement test has a normal distribution, a mean of 1000, and a standard deviation of 100. What per


Suppose you are dealt a hand of 3 cards twice. What is the probability that you will receive exactly 2 kings in each of the two deals? How many different combinations can there be, such that, you will be dealt exactly two kings?

Calculating probabilities.

Approximately 14 percent of the population of Arizona is 65 years or older. A random sample of five persons from this population is taken. The probability that less than 2 of the 5 are 65 years or older is: A bank lobby has four video cameras positioned to view the entire lobby. Any one of the four is sufficient to monitor th

Calculating probabilities: 3 questions.

1) The odds of the Dallas Cowboys winning this year's Super Bowl are 3 to 1. Compute the probability of the Cowboys winning a).33 b).25 c).75 d) none. 2) An appliance dealer calculated the proportion of new dishwashers sold that required various numbers of service calls to correct problems during the warranty period. The r

Systems Engineering or Statics for MTBF and probability of failure

Please review these attached Systems Engineering problems and provide assistance. The problems are related to Mean Time Between Failure and failure rates for systems. --------------------------------------------------------------------- 10. The failure rate (&#955;) of a device is 22 failures per million hours. Two standby


If A and B are independent events with P(A) = 0.25 and P(B) = 0.60, then P(A/B) is? 2. Intentions of customers regarding future automobile purchases and the financial capability of the consumers are given below: Plan to buy qualify for within 6 6 months or

Probability ...

1. The salaries (in thousands of dollars) for a sample of 13 employees of a firm are: 26.5, 23.5, 29.7, 24.8, 21.1, 24.3, 20.4, 22.7, 27.2, 23.7, 24.1, 24.8 and 28.2. Compute the variances. 2. New York City is estimated to have 21 percent of the homes with TV sets served by cable TV. If a random sample of four is taken f

Statistics - Probability..

In a bag there are 20 marbles. The colors of the marbles are as follows: red - 5; blue - 8; green - 3; yellow - 4. a. What is the probability of selecting a red marble? b. What is the probability of selecting a blue marble? c. What is the probability of selecting a pink marble? None d. What is the probability of selectin


New Orleans Punch was made by Frutayuda, Inc., and sold in 16-ounce cans to benefit victims of Hurricane Katrina. The mean number of ounces placed in a can by an automatic fill pump is 15.8 with a standard deviation of 0.12 ounce. Assuming a normal distribution, what is the probability that the filling pump will cause an overflo

Probability - The length of time to complete a door assembly on ...

The length of time to complete a door assembly on an automobile factory assembly line is normally distributed with mean 6.7 minutes and a standard deviation 2.2 minutes. For a door selected at random, what is the probability the asembly line time will be between 5 and 10 minutes? Answer to 4 decimal places.

Understanding and calculating probabilities.

1. A certain company reduced its management staff from 18 managers to 12. The company claimed that the 6 managers were randomly selected for job termination. However, the 6 managers chosen are the 6 oldest managers among the 18 that were employed. What is the probability that when 6 oldest managers are randomly selected from

Probability: Discrete and Continuous Probability Distributions

What is a probability distribution and its purpose? Distinguish between discrete and continuous probability distributions. Give an example of each. What is randomness? Assume you have an Excel worksheet of the dimension, A1:E101. The first row contains data labels. How would you randomize the data file and to select a

Problems with probabilities

Please help with the following probability problem. A statistical experiment involves flipping a coin that is much thicker than a regular coin of the same diameter. When flipped, the probability for the thick coin to come to rest on its edge is 4 percent; otherwise it is a "fair coin" in the sense that we can get heads or ta

Simulation of probability distributions

Every 5 minutes a satellite sends an almost instantaneous signal burst to a ground station to communicate that all systems are working properly. The satellite will not transmit the burst if there is an error somewhere. The transmitted signal strength is 4 units. The signal received at the ground station is a combination of the t

Fault Tree Problem: Calculating probabilities.

Assume the probability of a tire blowout is 0.178% per 50,000 miles of use and that a person travels 15,000 miles per year in a car. Assume that the probability of loss of control is 60% if the blowout occurs on the front tires and 20% for the rear tires. If control is lost, the probability is 50% of veering to the right and 50%

Conduct a simulation for 20 copier arrivals assuming that the system starts empty. Use the Excel random number function to determine the inspection times. Calculate the average time a copier spends in the system based on these 20 arrivals.

Ricon, Inc. uses an assembly line to produce its office copiers. The final step in the assembly process is quality control inspection. Copiers arrive at the quality inspection area exactly every 90 seconds. The time it takes to perform a quality control inspection follows an exponential distribution, with a mean of 72 seconds

Understanding waiting line models

Please see attached for fully formatted questions. ---------------------------------------------------------- 1. a. The expected number of customer that will arrive in a five minutes period is b. The probability that exactly 0,1,2 and 3 customer will arrive during a five minutes period is c. The probability of delays will

Probability ...

It has been reported that the average US office worker receives 14 fax messages per day. For purposes of this exercise, we will assume that the daily number of fax messages is normally distributed with a standard deviation of 5.0 messages. For an office in which 10 workers are employed and considering these person as a simple


For a random variable that is normally distributed, with u = 200 and o = 20, determine the probability that a simple random sample of 4 items will have a mean that is: a. greater than 210 b. between 190 and 230 c. less than 225

Normal distributions: Z scores and probabilities

A continuous random variable, x, is normally distributed with a mean of $1000 and a standard deviation of $100. Convert each of the following x values into its corresponding z-score. a. x = $1000 b. x = $750 c. x = $1100 d. x = $950 e. x = $1225 2.Using the standard normal table, find the following probabilities

Statistics - Probability of Business Failures

The following data represent x = the total number of business and y = the number of business failures in mountain states over a 1-year period. x = Number of y = Number of State businesses business failures Arizona 146.67

Finding probabilities with the help of binomial distribution

A regional manager visits local fast-food franchises and evaluates the speed of the service. If the manager receives her meal within 45 seconds, the server is given a free movie-admission coupon. If it takes more than 45 seconds, the server receives nothing. Throughout the company's franchises, the probability is 0.60 that a

Simulation Model

Problem #19 Customers arrive at the Blinkies Donut shop between 6:30am and 8:30am according to a Poisson process with a mean rate of one every minute. Seventy percent of the arriving customers purchase one or two donuts, while 30% purchase the Blinkies Dozen pack. For customers purchasing one or two donuts, the service time