Homework Help

x 1 2 3 4  P(x) .54 0.16 0.06 0.04 0.20 calculate mean value of x and probability that...

user profile pic

j1195059 | Student, Undergraduate | (Level 2) eNoter

Posted November 2, 2010 at 8:11 AM via web

dislike 0 like

x 1 2 3 4  P(x) .54 0.16 0.06 0.04 0.20 calculate mean value of x and probability that x exceeds its mean value.

not sure what to do. any help would be great!

1 Answer | Add Yours

user profile pic

sociality | High School Teacher | (Level 1) Valedictorian

Posted November 2, 2010 at 6:35 PM (Answer #1)

dislike 2 like

You have only provided 4 values of x, so I am taking the 5th value of x as 5.

So we now have the values of x as 1, 2, 3, 4 and 5 and their probabilities as 0.54, 0.16, 0.06, 0.04 and 0.20.

Now the mean value of x is calculated as the sum of the products of the value of x with the respective probability. Here that is the sum:  1*.54+ 2*0.16+ 3*0.06+ 4*0.04 + 5*0.2 = 0.54+ 0.32+ 0.18+ 0.16+ 1 = 2.2

The mean value of x is 2.2

The values of x greater than 2.2 are 3, 4 and 5. The probabilities of x being either of them is 0.06 + 0.04 + 0.2 = 0.3

The probability that x exceeds its mean value is 0.3

Join to answer this question

Join a community of thousands of dedicated teachers and students.

Join eNotes