Search
The time until a chemical reaction is complete (in milliseconds) has the density function f(x) = e^-x/100/100 for x ≥ 0.
a. Determine the mean and variance of x.
b. P(X>100).
There are 250 dogs at a dog show that weight an average of 12 pounds, with a standard deviation of 8 pounds .If 4 dogs are chosen at random, what is the probability that the average weight is greater then 8 pounds
Suppose f(x) = 3x^2/2 for - 1 < x < 1. Determine the mean and variance of X.
A population consists of the four numbers {2, 3, 6, 9}. Consider all possible samples of size 3 can be drawn without replacement from this population. Find the following:
a. mean of the population
b. population variance
c. standard deviation of the population
d. mean of the sampling distribution of means
e. the standard deviation of the sampling distribution of means
f. List down all the possible samples of size 3.
g. construct a sampling distribution
The average preschool cost for tuition fees last year was 17,250. The following year, 20 institutions had a mean of 16,150 and a standard deviation of 2,250 is there sufficient evidence at =0.10 level of significance to conclude that the mean cost has increased?
Find the variance of the expected value of the probability distribution, X={1, 2, 3, 4, 5} P(X)={.10, .35, .15, .23, .17}
Two coins are tossed simultaneously. The outcome of the first coin is head. Let x be a random variable that denotes the number of heads that appear. What are the possible value of x?
A golfer playing a new course encounters a hole that requires a drive of 145 yards to successfully clear a pond. She knows that her drives are normally distrib- uted with a mean of 155 yards and a standard devia- tion of 9 yards. What is the probability that after her drive her golf ball will be at the bottom of the pond?
P ( -2.81 < z < 0 )
If three coins are tossed, what are the mean, variance, and standard deviation of the number of heads that occur?
