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Problem: Scores for SAT normally distributed with mean of 531 and standard dev. of 114. If college includes minimum score of 600 among requirements, what % do NOT satisfy requirement? Also, graph.

Probability Distribution Function

Suppose that the random variable y is described by the following probability distribution function: f(y) = 2/9y for 0<or=y<or=3 and it is 0 elsewhere. a.) Find P(0.50<or=y<or=1.50) b.) Find the mean and variance of y.


A study of vehicle flow characteristics on acceleration lanes found that one out of every six vehicles uses less than 1/3 of the acceleration lane before merging into the traffic. Suppose we monitor the location of the merge for the next 5 cars that enter the acceleration lane. a.)What is the probability that none of the veh


A committee has 6 grad students (4 are men), 8 undergrads (5 are men) and 3 faculty members (1 is a man). If 1 member is selected randomly, what is the P of getting a grad student or a man?


Scott gets a hit in 32% of the hits at bat. He bats 4 times in a game (assume each at bat is independent of the others). a) What is the chance he gets a hit in all 4 at bats? b)What is the chance he gets at least 1 hit?

Probability questions

a)Probablity an event is likely to occur? b) P of an impossible event? c) Sample space consists of 25 separate events equally likely. What is P of each? d) True/False test. P of correct if a random guess? e)Multiple choice test with 5 possible answers for each, P of getting correcdt of random guess?

Statistics problems

Please use Excel when necessary: Acording to a recent survey, 70% of all customers will return to the same grocery store. Suppose 10 customers are selected at random, What is the probability: a) Exactly 5 of the customers will return? b) All 10 customers will return? c) At least 7 of the customers will return? d) Less th


1, At Acme Inc., women employees are three times as likely to take advantage of computer training courses as men employees. Seventy percent of Acme's very large work force are women. a, What proportion of Acme employees who take advantage of computer training courses are women? b, Twelve percent of the workforce at Acme ta


Gas Station pump signs, at one chain, encourage customers to have their oil checked, claiming that one out of every four cars should have its oil topped. a.) What is the probability that exactly 3 of the next 10 cars entering a station should have their oil topped? b.) What is the probabily that at least half of the next


If the probability that an individual suffers a bad reaction from injection of a given serum is 0.001, determine the probability that out of 2000 individuals; a.) Exactly 3 b.) More than 2 individuals will suffer a bad reaction.


Insurance probability tables, as the one on the attachment, tabulates the average # of American males per 100,000 who will die during various age intervals. E.G., out of 100,000 male babies born alive, 1,527 will die before their first birthday. Answer following w/ table: a.) What is the probability that a newborn male will

Simple Arrangment Possibilities

4 different math books, 2 different Chemistry books, and 6 different physics books are arranged on a shelf. How many different arrangements are possible if: a.)The books in each particular subject must stand together? b.)Only the math books must stand together?


In a true experimental study, the subjects should be assigned to groups randomly. If this is not possible, and a researcher uses stratified sampling, the groups are sampled individual according to a _______________system based on the proportion of the subgroup in the population as a whole. On a multiple choice test, there a

Only for OTA 103997

Only for above listed OTA. Female candidates for flight school have times normally distributed with a mean of 0.65 seconds and a stan. dev. of 0.15 seconds. If 25 candidates are randomly selected, find probability their mean reaction time is less than 0.70 seconds. Answer is .9525

Only OTA 103997

Only above listed OTA Replacement time for tv sets normally distributed with a mean of 8.2 years and a stan. dev. of 1.1 years. a) Find probability that a randomly selected set will have a replacement time less than 5.0 years b) If you want to provide a warranty so that only 1% of the sets will be replaced before the warranty

Only for OTA 103997 or 103300

Only for above listed OTA's. Assume weights normally distributed with mean u=143 lb. and standard deviant o=29 lb. Assume randomly selected. Draw graph and find indicated probability. P(150 lb < x < 180 lb).


Subject: Telecommunication system statistics Details: A unit for a telecommmunication system is to be designed so that the probability that it fails during a period of five years does not exceed 0.4. the unit is to be made up of (n) effectively identical componants each with an exponential failure distribution and a hazard rat

Toy store stock decisions

1. The manager of a toy store has to decide how many toys to stock for the Christmas season. Each toy cost the store $5 and is sold for $10. The manager is certain that total sales of a particular toy will always be either 1,000 units, 2,000 units, 3000, 4000, or 6,000 units. The manager has to decide whether to order 2,000, 4,0

Standard Deviation

Question was asked previously and the calculations not detailed enough for me to determine how the answer was received. Please provide detailed explanation - I got a different answer and I KNOW mine is not right! Question: A manufacturing process produces units that average 10 inches in length with a standard deviation of 3

Stats questions

1.) A recent survey by the American Accounting Association revealed 23 percent of students graduating with a major in accounting select public accounting. Suppose we select a sample of 15 recent graduates. a. What is the probability two select public accounting? b. What is the probability five select public accounting? c. H

Given that an even number occurred, the probability that it was a 4 is?

Question 2: Using the normal approximation to the binomial to approximate the probability that X is at least 10, the area under the normal curve should be calculated from? Question 1: A die was tossed. Given that an even number occurred, the probability that it was a 4 is? Question 3: A coin is tossed 1,000 times. The probab

Probability Formula

A group of 30 people gather in a room. What is the probability that at least 2 of these people have the same birthday? The year of birth is not considered; having the same birthday means two peple were born on the same day of the year.