The range of a random variable X is { 1 , 2 , 3 … . . . } and P ( X = x ) = c x x ! , for x = 1 , 2 ,…

The range of a random variable X is {1,2,3...} and P(X=x)=cxx!, for x=1,2,3, Then the value of C is
  1. 0
  2. 1
  3. ln(2) (where ln denotes the natural log )
  4. ln(3) (where ln denotes the natural log )

Solution

Given: PX=x=cxx!

 PX=1

 c+c22!+c33!+.....=1

 1+c+c22!+c33!+...... =2

 ec=2

 clogee=loge2

c=ln2

Asked in: AP EAMCET 2021 (20 Aug Shift 2)

Practice more Probability questions on Aicharya