English

The p.d.f. of a continuous r.v. X is f(x) = {3x280<x<20otherwise.Determine the c.d.f. of X and hence find P(1 < X < 2) - Mathematics and Statistics

Advertisements
Advertisements

Question

The p.d.f. of a continuous r.v. X is

f(x) = `{((3x^2)/(8), 0 < x < 2),(0, "otherwise".):}`
Determine the c.d.f. of X and hence find P(1 < X < 2)

Sum

Solution

F(x) = `int_0^xf(x)*"d"x`

= `int_0^x (3x^2)/(8)*"d"x`

= `(3)/(8) int_0^x x^2*"d"x`

= `(1)/(8)[x^3]_0^x`

= `x^3/(8)`

P(1 < X < 2) = F(2) – F(1)

= `(2)^3/(8) - (1)^3/(8)`

= `1 - (1)/(8)`

= `(7)/(8)`

shaalaa.com
Probability Distribution of a Continuous Random Variable
  Is there an error in this question or solution?
Chapter 8: Probability Distributions - Exercise 8.2 [Page 145]

APPEARS IN

Balbharati Mathematics and Statistics 2 (Commerce) [English] 12 Standard HSC Maharashtra State Board
Chapter 8 Probability Distributions
Exercise 8.2 | Q 1.09 | Page 145

RELATED QUESTIONS

It is known that error in measurement of reaction temperature (in 0° c) in a certain experiment is continuous r.v. given by

f (x) = `x^2/ 3` , for –1 < x < 2 and = 0 otherwise


Solve the following :

The following probability distribution of r.v. X

X=x -3 -2 -1 0 1 2 3
P(X=x) 0.05 0.10 0.15 0.20 0.25 0.15 0.1

Find the probability that

X is non-negative


Solve the following :

The following probability distribution of r.v. X

X=x -3 -2 -1 0 1 2 3
P(X=x) 0.05 0.10 0.15 0.20 0.25 0.15 0.1

Find the probability that

X is even


Check whether the following is a p.d.f. 

f(x) = `{(x, "for"  0 ≤ x ≤ 1),(2 - x, "for"  1 < x ≤ 2.):}`


Check whether the following is a p.d.f.

f(x) = 2  for 0 < x < q.


The following is the p.d.f. of a r.v. X.

f(x) = `{(x/(8),  "for"  0 < x < 4),(0,  "otherwise."):}`

Find P(X > 2)


Suppose error involved in making a certain measurement is a continuous r. v. X with p.d.f.

f(x) = `{("k"(4 - x^2),  "for" -2 ≤ x ≤ 2),(0,  "otherwise".):}`
compute P(X > 0)


Following is the p. d. f. of a continuous r.v. X.

f(x) = `{(x/8,  "for"  0 < x < 4),(0,  "otherwise".):}`
Find expression for the c.d.f. of X.


The p.d.f. of a continuous r.v. X is

f(x) = `{((3x^2)/(8),  0 < x < 2),(0, "otherwise".):}`
Determine the c.d.f. of X and hence find P(X > 0)


Choose the correct alternative :

Given p.d.f. of a continuous r.v.X as f(x) =  `x^2/(3)` for –1 < x < 2 = 0 otherwise then F(1) = _______.


State whether the following is True or False :

If X ~ B(n,p) and n = 6 and P(X = 4) = P(X = 2) then p = `(1)/(2)`


Solve the following problem :

In the following probability distribution of a r.v.X.

x 1 2 3 4 5
P (x) `(1)/(20)` `(3)/(20)` a 2a `(1)/(20)`

Find a and obtain the c.d.f. of X.


Solve the following problem :

Suppose error involved in making a certain measurement is a continuous r.v.X with p.d.f.

f(x) = `{("k"(4 - x^2), "for" -2 ≤ x ≤ 2),(0, "otherwise".):}`
Compute P(X < – 0.5 or X > 0.5)


Solve the following problem :

Determine k if the p.d.f. of the r.v. is

f(x) = `{("ke"^(-thetax),  "for"  0 ≤ x < oo),(0, "otherwise".):}`
Find `"P"("X" > 1/theta)` and determine M is P(0 < X < M) = `(1)/(2)`


Solve the following problem :

The p.d.f. of the r.v. X is given by

f(x) = `{("k"/sqrt(x), "for"  0 < x < 4.),(0, "otherwise".):}`
Determine k, the c.d.f. of X, and hence find P(X ≤ 2) and P(X ≥ 1).


For the following probability density function of a random variable X, find P(X < 1).

`{:(f(x) = (x + 2)/18,";"  "for" -2 < x < 4),(               = 0,","  "otherwise"):}`


If the p.d.f. of X is

f(x) = `x^2/18,   - 3 < x < 3`

      = 0,        otherwise

Then P(X < 1) is ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×