An experiment consists in asking 8 people whether they have a college degree, and counting the number of people who answer they do have one. List all the possible values of the random variable associated to this experiment.
Sample space contains 8 people.
Let X = number of people who have a college degree.
Then X can takes the values 0,1,2,3,4,5,6,7 and 8. Zero corresponding to no one has college degree, ... , 8 corresponding to all of the eight people have college degree.
Therefore possible values of the random variable X are 0,1,2,3,4,5,6,7 and 8.
An experiment consists in asking 8 people whether they have a college degree, and counting the...
In one city, 20% of the population has a college education. Three people are selected at random from the city. Find the probability distribution of X, the number among the three that have a college education. A. Identify then and the p for this distribution. p B. Let the random variable x be the possible number of people selected with a college degree. Develop a binomial distribution by finding P(x) when x = 0, 1, 2, and 3. XP(x) 0...
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3- (20 points) A random experiment consists of simultaneously and independently flipping a coin five times and observing the n-5 resulting values facing up. The coin is biased with: P(heads) - 0.75 : P(tails) p-0.25 Define a Random Variable (RV) X equal to the number of fails that we observe during the flips. a) Give the probability P. that the random variable X will take on the value 3 ANSWER: P,= (simplified number) b) Give the mean of X, that...
In a survey of 1000 eligible voters selected at random, it was found that 200 had a college degree. Additionally, it was found that 90% of those who had a college degree voted in the last presidential election, whereas 46% of the people who did not have a college degree voted in the last presidential election. Assuming that the poll is representative of all eligible voters, find the probability that an eligible voter selected at random will have the following...
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A polling company takes a nationwide survey asking people
whether they favor stricter laws on the sale of cigarettes. They
find that 45% agree, 35% disagree, and 20% are undecided. In a more
local simple random sample of size 200, 110 say they favor stricter
laws, 60 are opposed, and 30 have no opinion. You're interested in
whether these results differ significantly from the national
findings. Which of the following gives the set of expected values
for the test for...
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