Hi. Glad to see that we're being reminded of the rules. Here's a question on random variables.

The discrete random variable X has a probability density function

$\displaystyle

P(X=x)= \frac{x}{10} where x= 1, 2, 3, 4

$

P(X=x) is 0 otherwise

If $\displaystyle Y $denotes the sum of two independent observations of $\displaystyle X$

Determine the value of $\displaystyle P(Y=4) $