Statistics and Probability Answers

The probability that a freshman entering AAU (Science Faculty) will survive first semester is 0.92. (From

1993/94 academic year statistics). Assuming this pattern remain unchanged over the subsequent years, what

is the probability that among 100 randomly selected freshmen in first semester,

a) None will survive?

b) Exactly 97 will survive?

c) At least three will survive?

Two dice are rolled. Let X be a random variable denoting the sum of the numbers

on the two dice.

i) Give the probability distribution of X

ii) Compute the expected value of X and its variance

Let A and B be two events associated with an experiment and suppose that P(A)=0.4 while P(AUB)=0.7. Let

P(B)=P

a) For what choice of P are A and B mutually exclusive?

b) For what choice of P are A and B independent?

In a large graduating class of 100 students 54 studied mathematics, 69 studied library science, and 35 studied

both mathematics and library science. If one of these students is selected at random, find the probability that

a) The student takes mathematics or library science

b) The student does not take either of these subjects

c) The student takes library science but not mathematics

In how many ways can a committee of three be chosen from 4 married couples if

a) All are equally eligible?

b) One particular man must be on the committee?

A population consists of the numbers 1, 2, 3, and 4 with the sample size of 2 (without replacement). Which mean that has a probability of 2/6 or 1/3 or 0.33?

If the events have the same theoretical probability of happening, then they are called

Consider a population consisting of the values (1, 3, 8), n= 2 with replacement.

1. Identify the probability of each sample

The time taken to assemble a car in a certain plant is a random variable having a normal

distribution of 20 hours and a standard deviation of 2 hours. What is the probability that a

car can be assembled at this plant in a period of time less than 19.5 hours?

1. If a population has a mean of 5.7, what is the mean of the sampling distribution of its means?