Recent content by TomJerry

Thanks , but my real concern is how will i get f(x) since i only know mean which is 0 so what i can do is f(x) = 0 and nothing else but not sure that the right way to go.

Hey chiro, I know that its mean is 0 that means xf(x) = 0 ...please help me with this...

Sorry for that , but since i have already posted it , could you please guide me on how to solve the last one ie E[X^3] = ?

Thanks X should be 49 and not 50 ...Isnt that correct

Thanks

I was able to figure out E[X^2] = 1 now i am stuck with getting the iii) question E[X^3] how should i do this ..

Question: X is normally distributed and the mean of X is 12 and standard deviation is 4 Find i)P(0<=X<=12) Solution P(X=12) = Z(12-12/4) =0 Stuck here! what to do next

Suppose X and Y are independent Poisson random variables, each with mean 1, obtain i) P(X+Y)=4 ii)E[(X+Y)^2] I m trying to solve this problem but have difficulty starting ... If some one could give me a some pointers

Question: The time in minutes , it takes to reboot a certain system is continuous random variable with density. f(x) = C(10-x^2), 0<= x <=10 ; = 0 , other wise i) compute C ii)Obtain the probability that it takes between 1 and 2 minutes to reboot. Solution : i) f(x) = \int_{0}^{10}...

Question: A new computer virus attacks a folder consisting of 200 files. Each file gets damaged with probability 0.2 independently of other files. Using Normal approximation of binomial distribution, find the probability that fewer than 50 files get damaged. Solution: Here n=200, p =0.2...

Question : Random variate X follows a normal distribution with mean 0 and variance 1 i.e.X~N(0,1). Given Y = 2X + 4, find i) E[Y] ii) Var(Y) iii) E[X^3] Solution: here E[X'] = 0 and V(X) = 1 i) E[Y] = E[2X+4] = 4 [Is this correct] ii) Var(Y) = E[Y2] - [E(Y)]2 =E[Y2] -16...

Need to know if the answer are correct or no

Question: Five persons in a group of 20 are grauduate. If 3 are picked out of 20 at random, i) compute the probability that all are graduate ii) find atleast one being graduate. Solution: i) P(all grauduate being selected) = 5C3 / 20C3 [Is this correct] ii) P(atleast 1 being...

Question: If X and Y are independent poisson variates with mean λ1 and λ2 respectively, what is the probability that i) X + Y =k ii) X = Y Solution: Dont know how to solve this .

Question : For the following probability distribution X | -1 | 0 | 1 | Y | 0 | 1/15 |2/15|1/15| 1 | 3/15 |2/15|1/15| 2 | 2/15 |1/15|1/15| Find i )The conditional distribution of X given Y=2 Solution f(x|2) = f(x,2) / h(2) How do i go about this without knowing f(x,2)