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Normal Distribution and Populations

Please help with the following problems involving normal distribution and populations. Based off the three requirements that must be met before an analysis of variance test (ANOVA) can be used: 1. Samples must be randomly selected from the populations to be evaluated. 2. All populations from which the samples are selected

Binomial random variable

A study consists of randomly selecting 14 newborn babies and counting the number of girls. If we assume that boys and girls are equally likely and if we let x=number of girls among 14 babies, then x is a random variable because its values depends on chance. The possible values of x are 0,1,2,...,14. The Below table lists the val

Probability: Expected Value and Decision Analysis

Expected Value and Decision Analysis: 1- In a certain state lottery, a lottery ticket cost $8. In terms of the decision to purchase or not to purchase a lottery ticket, suppose that the following payoff table applies: State of nature Decision alternative Wins s1 Lose s2 P

Probability and Logical Conclusion

Please provide formulas and logical conclusions for each. Include step by step calculations for each. 8. If the probability of having a boy is .47, find the following a. For families with 10 children i. The mean for the number of boys in a family ii. The standard deviation for the number of boys iii. The probability of h

Probability and Decision Making

1- A pharmaceutical company conducted a study to evaluate the effect of an allergy relief medicine. 200 patients with symptoms that included itchy eyes and a skin rash received the new drug. The results of the study are as follows: 90 of the patients treated experienced eye relief 135 had their skin rash clear up, and

Which would surprise you more: (1) she predicts at least 8 out of 10 correctly, or (2) she predicts at least 6 out of 10 correctly on each of 4 separate occasions? Answer by assuming that (1) she really is guessing and (2) each day the Dow is equally likely to go up or down.

A person claims that she is a fortune teller. Specifically, she claims that she can predict tha direction of the change (up or down) in the Dow Jones Industrial Average for the next 10 days (such as U, U, D, U, D, U, U, D, D, D). (You can assume that she makes all 10 predications right now, although that won't affect your answ

Picking a Card in a Game

A situation is presented where you have to pick the queen out of 3 cards, the other two are Aces. The person running the game asks you to pick a card, you do, and he turns over a card that you didn't pick to show it was an ace. He then offers you the choice to keep your card or choose the third card. Using your knowledge of p

The Probability for Electrical Power and Bond Funds

1. A certain airplane has two independent alternators to provide electrical power. The probability that a given alternator will fail on 1-hour flight is 0.02. What is the probability that (a) Both will fail? (b) Neither will fail? (c) One or other will fail? 2. The contingency table belo


1) Two cards are drawn from an ordinary deck of 52 cards find the probability of each event showing your reasoning carefully a. two aces b. two red cards c. two red aces d. two honor cards (A, K, Q, J, 10). 2) A certain airplane has two independent alternators to provide electrical power the probability that a given alt

What percent of the flights are sold out? On what percent of the flights does the airline make money? Below what number of passengers on a flight will the airline reduce the number of flight attendants?

Landrum Airline flies the route between Chicago and Pittsburgh. The mean number of passengers per flight is 160 with a standard deviation of 20. The aircraft used for the route has 200 seats. a. What percent of the flights are sold out? b. The airline must sell 150 seats to break even on this particular flight. On what perce

Continuous Probability Distributions: Normal Distribution

Fast Service Truck Lines uses the Ford Super Duty F-750 exclusively. Management made a study of the maintenance costs and determined the number of miles traveled during the year followed the normal distribution. The mean of the distribution was 60,000 miles and the standard deviation 2,000 miles. a. What percent of the Ford S


Find the probability P(z < -0.46) using the standard normal distribution. A) 0.5400 B) 0.6772 C) 0.3228 D) 0.8228

Normal distribution ...

WNAE, an AM station totally dedicated to deliver news, found that while the Distribution of listeners tune in the station follows the normal Distribution. Distribution of the average is 15.0 minutes and standard deviation is 3.5. What is the probability that a particular listener in tune to the station at: a)more than 20 minute

Calculation of probability based on Z score

A normal population has an average of 80 and a standard deviation of 14.0. Calculate the probability of a value between 75.0 and 90.0. Calculate the probability of a value of 75.0 or less. Calculate the probability of a value between 55.0 and 70.0.

Probability Calculation Problem Based on Binomial Distribution

According to an Internet posting, 80% of adults enjoy drinking beer. If a group of 3 adults is selected at random, find the probability that none of them enjoy drinking beer. Place your answer, rounded to three decimal places, in the blank. Simply provide the numerical value. For example, 0.123 would be a legitimate entr

Understanding Probability

1. A Motor Company has purchased steel parts from a supplier for several years and has found that 10% of the parts must be returned because they are defective. An order of 25 parts is received. What are the mean and standard deviation of the defective parts? A) Mean = 3.5; standard deviation = 2.5 B) Mean = 2

A. Find the overall proportion of hits, and identify the length of the longest streak of hits and the length of the longest streak of misses. Write a paragraph commenting on your proportion of hits and your "streaks." b. Describe how the "streaks" compare for the 50-percent and 75-percent scenarios.

A certain college's men's basketball team is quite accomplished at making free throws. According to the coach, in their most recent season the team made approximately 75 percent of free-throw attempts, and ranked 10th in the country among similar schools in successful free-throw attempts. Set up another new worksheet to simulate

Mean Weight of Plain Candies

Labeling of M&M Packages Q. M&M plain candies have a mean weight of 0.9147 g and a standard deviation of 0.0369 g (based on Data Set 19 in Appendix C). the M&M candies used on Data Set 19 came from a package containing 1498 candies, and the package label stated that the net weight is 1361 g. (If every package has 1498 cand

Probability problems

1) Find the probability (type answer as an integer or simplified fraction) of a couple having a baby boy when their fifth child is born, given that the first four children were all boys. Assume boys and girls equally likely. Is the result the same as the probability of getting all boys among five children? 2) When designing

Probability: Failures, Least Amounts and Joint Probability

1. There are five computers in an office. The probability of failure of a computer is 0.3. What is the probability that (a) there are 3 computers working, and (b) at least three computers working? 2. A computer service company is interested in the number of computers that fail. There are hundreds of computers in use in their

Statistics Normal Distribution

Assume that the population of heights of male college students is approximately normally distributed with a mean "m" of 68 inches and standard deviation "s" of 3.75 inches. A random sample of 16 heights is obtained: 1.) Describe the distribution of x, height of the college student. 2.) Find the proportion of male college

Power of a Statistical Test

The power of a statistical test is?: 1) the probability of not rejecting H o when it is false 2) the probability of rejecting H o when it is false

A Description of Normal Probability

The Director of Emergency Medicine at Big Mountain Medical Services is studying patient waiting time. Waiting time is defined as the time from when a patient enters the facility until seen by a physician. The study indicates the waiting time follows a normal distribution with a mean of 22 minutes and a standard deviation of 8 mi

STATISTICS: According to a study the popular belief is 80% of adults enjoy ...

1. According to a study the popular belief is 80% of adults enjoy drinking beer. If 3 adults were chosen at random from this study, what would the probability be that none of them enjoy drinking beer? Explain how you found your answer. 2. A family has 5 children and 1 of them is a boy...the percentage of boy is 1/5, or .020

Quantitative Decisions: Statistics, Probability, and Game Theory

Please see the attached document for properly formatted questions. 1. Nick has plans to open some pizza restaurants, but he is not sure how many to open. He has prepared a payoff table to help analyze the situation. States of Nature Alternatives Good Market Fair Market Poor Market Open 1 380,000 70,000 -400,000 Op

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?