AP EAMCET20225 Jul 2022Evening ShiftMathematicsProbabilityActual
It is given that the discrete random variable is X B(n, p) and P(X=2)=P(X=3) .
Options
- A2-p
- B3-p
- Cp -2
- Dp-3
Correct answer
B. 3-p
Step-by-step solution
P (x=2)= P (x=3) ^n C₂ p^2 q^ n -2 = ^n C₃ p^3 q^ n -3 aligned & n ! 2 !(n-2) ! p^2 q^n q^2 = n ! 3 !(n-3) ! p^3 q^n q^3 & 1 n-2 = p 3 q & 3 q=p(n-2) & q=1-p & 3(1-p)=n p-2 p & n p=2 p+3(1-p) aligned aligned & =2 p+3-3 p & =3-p aligned mean =3-p