The probability that X can take the values $x_i$ has the following form: $P\left(X=x_i\right)=\left\{\begin{array}{lll} 0.2 & \text { if } ~~~x_i=0 \\ k x_i & \text { if } ~~~x_i=1 \text { or } 2 \\ k\left(5-x_i\right) & \text { if } ~~~x_i=3 \\ 0 & ~~~~~~\text { otherwise } \end{array}\right.$ The value of P(X = 2) is: |
$\frac{4}{25}$ $\frac{3}{25}$ $\frac{6}{25}$ $\frac{8}{25}$ |
$\frac{8}{25}$ |
The correct answer is Option (4) → $\frac{8}{25}$ $∑P(x_i)=1$ $⇒0.2+k×1+k×2+k×(5-3)+0=1$ $⇒0.2+k+2k+2k=1$ so $5k=0.8$ so $k=\frac{0.8}{5}=\frac{4}{25}$ so $P(x=2)=2k=\frac{8}{25}$ |