Math Answers

Let X be a ramdom variable with the following probability distribution

x: 1, 2, 3, 4

P(X=x): 0.4, 0.3, 0.2, 0.1

a. Find E(X) and Var(X)

b. is E(X) a possible value of X

Given the data 6, 9, 12, 15, 16, 19, 22. Construct a sampling distribution of the sample mean without replacement and repetition by selecting 2 samples at a time.

A family has four children. If Y is random variable that pertains to the number of female children what are the possible values of Y?

Determine if the following functions are continuous or discontinous at the given value of x.

1. f(x)= 3x+2x+1 at x= -2

2. f(x)= 9x2-1 at x=1

3. f(x)= 1/x-2 at x=2

4. f(x)= x-1/x^2 -1 at x=1

5. h(x)= x+1/x-1at x=1

6. f(x)= x^2 -2x+1 at x=3

7. f(x)= x/(x+2)(x-3) at x=2

8. f(x)= |x| at x=0

9. f(x) Cube root√x^2 -4 at x=5

10. f(x)= x+1/x-1 at x=0

A shipments of five computers contains that are slightly defective. If a retailer receives three of these computers at random list the elements of the sample space 5 using the letters D and N for defective and non-defective computers respectively. To each sample point assign a value x of the random variable X representing the number of computers purchased bu the retailer which are slightly defective

a sample of 150 students were chosen at random from grade 11 students who have laptops.Pampanga. the sample indicated that 75% of them were in favor of having an educational trip. find a) 95% and b) 99% confidence intervals for the proportion if all students who are in favor having an educational trip

in a random sample of 120 teachers, 48 of them have master's degree find the value o p

in a random sample of 120 teachers 48 of them have master's degree. find the value of p

From a box containing 4 black balls and 2 green balls,3 balls are dawn in succession. Each ball is placed back in the box before the next draw is made. Let G be a random variable representing the number of green balls that occur. Find the values of the rabdom variable G

In a triangle side x is 3/5 if side z. If y is 3/4 of side x,. What is the ratio of y to z?