A random variable X has the following probability distribution : X 1 2 3 4 5 6 7 P(X) $C$ $2C$ $2C$ $3C$ $C^2$ $2C^2$ $7C^2+C$ Then the value of C is :

$\frac{1}{10}$ $\frac{1}{5}$ $\frac{3}{10}$ -1

$\frac{1}{10}$

The correct answer is Option (1) → $\frac{1}{10}$ $∑P(X)=1$ $9C+10C^2=1$ so $10C^2+9C-1=0$ $10C^2+10C-C-1⇒(10C-1)(C+1)=0$ $C≠-1$ so $C=\frac{1}{10}$