Statistics and Probability Answers

If a freshman is selected at random to become student assistant what is the probability of selecting a student with an IQ between 90 and 120

Suppose that a population of women heights is normally distributed with mean of 68

inches and standard deviation of 3 inches. If a person is selected at random, what is the

probability that her height is less than 66 inches?

Suppose it is known that 10% of the owners of two year old automobiles have had problems with their electrical system. Compute the probability of finding exactly 2 owners that have had electrical system problems out of a group of 10 owners?

The joint density function of the random variables X1, X2, X3 is given as

f(x1, x2, x3) = {

c(x1 + 2x2 + 3x3), 0 < xi < 1, i = 1, 2, 3

0, elsewhere

Determine

(i) the value of c

(ii) the joint marginal density function of X1 and X2.

If the confidence interval is given as 90%, 93%, 96% and 98%. Find the value of z. Round the answer to the two decimal places.

A normal population has a mean of 50 and standard distribution of 10. Selecting 16 sample compute probability of sample mean

a) greater than 60

b) less than 45

c) between 45 and 60

A populations consists of the following five values: 2, 3, 5, 7, 10.

List all possible sample of size 3.

samples of three cards are drawn at random from a population of six cards numbered from 1 to 6. Construct the sampling Distribution of Sample means.