1. ## Dice problem

A dice is repeatedly rolled.
Suppose
$X=$ number of rolls necessary to obtain a $6$
$Y=$ number of rolls to get a $5$

How do you find $E[X\mid Y=1]$

2. You need to figure out the discrete distribution of $P(X=x\mid Y=1)$ for x=2,3,4,5,6.....

Then $E[X\mid Y=1]=\sum_{x=2}^{\infty} x P(X=x\mid Y=1)$