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Normal Distribution, Probability Density Function, Frequency Distribution

Dear OTA, Please explain with necessary steps. Thanks 1. In its standardized form, the normal distribution: A. has a meaning of 0 and a standard deviation of 1 B. has a mean of 1 and a variance of 0 C. has a total area equal to 0.5 D. is left-skewed 2. If a particular data set is approx. normally distributed, we

Normal Probability

The annual income of a large group of supervisors at Belco Industries follows the normal distribution. The mean amount earned yearly is $48,000 and the standard deviation is $1,200. The length of service of the same supervisors also follows the normal distribution, with a mean of 20 years and a standard deviation of 5 years. Joh

Retread Tire Company

2. The Retread Tire company recaps tires. The fixed annual cost of the recapping operation is $60,000. The variable cost of recapping a tire is $9. The company charges $25 to recap a tire. a. For an annual volume of 12,000 tires, determine the total cost, total revenue, and profit. b. Determine the annual break-even volume

Simple Probability with Contagious Diseases

Consider 5 families, each consisting of 4 persons. If it is reported that 6 of 20 individuals in these families have a contagious disease, what is the probability that at least 3 of the families will be quarantined.

Determining Probabilities - Ancorage, Alaska

If you can show me how you did each step that would be great. Assume that the population of Ancorage, Alaska is 265,000. The City of Anchorage is made up of 40% Females. Further assume we take a random sample of 11 individuals. (Assume 60% are Males).Determine the probabilties. A.That all are males B.Thats between 5 and

A grocery chain wants to taste-test a private label cola drink.

A grocery chain wants to taste-test a private label cola drink. A tester is given eight unmarked glasses, four containing the private-label drink and four containing a nationally advertised cola. The tester is asked to identify the four glasses containing the private-label drink. How many different choices of four glasses can

Multiple Choice - What scale of measurement are these numbers considered?

1-1 The members of each basketball team wear numbers on the back of their jerseys. What scale of measurement are these numbers considered? A. Nominal B. Ordinal C. Interval D. Ratio E. None of the above 1-2 Respondents were asked, "Do you now earn more than or less than you did five years ago?" What is this level

Important information about Probability and Distributions

- What is the gender distribution (% females and % males)? - What is the "tenure with company" distribution by gender? - What % of the survey participants are in each department? - What is the mean overall satisfaction by gender? - If we choose a person at random from this database: o What is the probability that this

Probability - The Journal News

In the July 29, 2001 issue of The Journal News (Hamilton Ohio) Lynn Elber of the Associated Press reported on a study conducted by the Kaiser Family Foundation regarding parents' use of television set V-chips for controlling their children's' TV viewing. The study asked parents who own TV's equipped with V-chips whether they us

Poisson and exponential distributions

Please see attached file for full problem description. The maintenance department of a factory claims that the number of breakdowns of a particular machine follows a Poisson distribution with a mean of two breakdowns every 500hours. Let x denote the time (in hours) between successive breakdowns. a. Find lambda and mu(x)


1. Store A, B, and C have 50, 75, and 100 employees, respectively. At store A 50% of the employees are women, at store B 60 % of the employees are women, and at store C 70% of the employees are women. Resignations are equally likely for all employees, regardless of gender. One employee resigns, and this employee is a woman. What

Probability and Weibull Distribution

Assume the life of a rotating item follows a Weibull distribution with the shape parameter (or slope) = 2 and the scale parameter = 10,000 hours. a. Determine the probability that the rotating item lasts at least 8000 hours. b. Determine the mean time until failure of the item. c. If 10 rotating items are used in a larger com

A Probability Distribution Question

It was found that jet pilots blackout threshold are X~N(4.5g, .7g) If only the top 25% allowed to apply to be astronauts, what is the cut off point FindP(X>x)=.25

Explaining probability

The mean time between reoccurring events is exponentially distributed with a mean time between events of 15 minutes. a. What is the probability that there are no events within a 30-minute period? Answer 0.00043 ? b. What is the probability that at least one call arrives within a 10-minute interval? Answer 0.4866 ? c. Wha

Probability and Statistical Analysis of Products

1. At a factory, the fill volume of Coke cans is normally distributed with a mean of 12.4 fluid ounces and a standard deviation of 0.1 fluid ounce. a. What is the probability a fill volume is less than 12 fluid ounces? b. If all Coke cans less than 12.1 or greater that 12.6 ounces must be destroyed, what proportion of Coke

Question about Probability for normal distribution

1. Find the probability that a standard normal random variable will assume a value between: a. z = 1.5 and z = .75 b. Greater than 1.25 c. Find a z such that 70% of the area is above that value. 2. In recent years, the use of the telephone as a data collection instrument for opinion polls has been steadily incr

Determining Probability

If you are told that a randomly selected mystery person was born in the 1990's, what is the probability of guessing his/her exact birth date (including year)?

28) A contractor is considering a sale that promises a profit of $ 23,000 with a probability of 0.7 or a loss (due to bad weather, strikes, and such) of $ 13,000 with a probability of 0.3. What is the expected profit? 29) Choosing 3 marbles from a box of 40 marbles (20 purple, 12 red, and 8 green) one at a time with replacement, keeping track of the number of red marbles chosen. Use the binomial probability formula to find the probability of x successes given the probability p of success on a single trial. 33) n = 4, x = 3, p = 1/6 34) n = 10, x = 2 , p = 0.5 35) n =12, x = 5, p = 0.25 36) A test consists of 10 true/false questions. To pass the test a student must answer at least 7 questions correctly. If a student guesses on each question, what is the probability that the student will pass the test? 37) Find the probability of at least 2 girls in 10 births. Assume that male and female births are equally likely and that the births are independent events. 38) An airline estimates that 98% of people booked on their flights actually show up. If the airline books 76 people on a flight for which the maximum number is 74, what is the probability that the number of people who show up will exceed the capacity of the plane? Find the mean, μ, for the binomial distribution which has the stated values of n and p. Round answer to the nearest tenth. 39) n = 33; p = .2 Find the standard deviation, σ, for the binomial distribution which has the stated values of n and p. Round your answer to the nearest hundredth. 41) n = 36; p = .2 42) n = 2661; p = .63 43) n = 94, p = 0.20 44) n = 377, p = 2/3 45) According to a college survey, 22% of all students work full time. Find the mean for the number of students who work full time in samples of size 16. 46) A company manufactures batteries in batches of 29 and there is a 3% rate of defects. Find the mean number of defects per batch. Determine if the outcome is unusual. 47) A survey for brand recognition is done and it is determined that 68% of consumers have heard of Dull Computer Company. A survey of 800 randomly selected consumers is to be conducted. For such groups of 800, would it be unusual to get 481 consumers who recognize the Dull Computer Company name? 48) According to AccuData Media Research, 36% of televisions within the Chicago city limits are tuned to "Eyewitness News" at 5:00 pm on Sunday nights. At 5:00 pm on a given Sunday, 2500 such televisions are randomly selected and checked to determine what is being watched. Would it be unusual to find that 872 of the 2500 televisions are tuned to "Eyewitness News"?

Solve the problem. 22) Find the variance for the given probability distribution. 22) ______ A) 2.46 B) 2.69 C) 7.43 D) 2.63 23) Find the standard deviation for the given probability distribution. 23) ______ A) 1.71 B) 1.6

21 prob/stats multiple choice questions

Express the indicated degree of likelihood as a probability value. 1) "You have a 50-50 chance of choosing the correct answer." 1) _______ A) 50 B) 0.50 C) 0.9 D) 0.25 2) "It will definitely turn dark tonight." 2) _______ A) 0.67 B)

Probability of weight distribution of gerbil

The state's smallest animal is a red-tailed gerbil, with a mean weight of 2.5 grams and a standard deviation of 0.25 grams. Assuming that the weights are normally distributed, find the probability of randomly selecting a gerbil that weighs a. between 1.0 and 2.0 grams b. between 1.6 and 2.2 grams c. more than 2.2 grams

Bayes' Theorem for Probability Revision

Set up a short problem related to your work environment to calculate the probability(ies) of an event happening. Then use Bayes' Theorem to revise the probability. Show all your work.


A company has a 99% chance of correctly identifying defective items and a 0.5% chance of incorrectly saying a good item is defective. The company has evidence that its production is 0.9% defective. a.) What is the probability that an item selected for inspection is classified as defective? b.) If an item randomly selected i

Discrete & Continuous Probability Distributions

Please use Excel for this and could you send me a few notes with step by step break-down on how to make it easy to figure out next time? 1. An American Society of Investors Survey found that 30% of individuals have used a discount broker. In a random sample of 9 individuals, what is the probability That: a. Exactly 2 of t

Find probabilities from a data set

Please answer the following probabilities from the data set below using Excel. Also please add them to the chart, Thanks. ? What is the gender distribution (% females and % males)? ? What is the "tenure with company" distribut

Statistics - probability

(1) The average number of humming birds per hour on a particular feeder is 5. Find the probability that exactly 3 humming birds feed during a particular hour using the correct table or formula. (2) Weights for students applying to a Sumo wrestling school are normally distributed, with a mean of 250 pounds and a standard dev

Real Estate Stats Confidence Interval

Assume you have a real estate investor client who wants you to answer some specific questions about housing in the neighborhood encompassed by the 5 townships in your Real Estate Data Set. Further assume that you have collected this random sample in an effort to answer your client's questions using statistical tools.: 1. Des