- #1

- 11

- 0

**Basic Probability Question—Rolling Die!!!**

## Homework Statement

Suppose you roll a fair six-sided die repeatedly until the first time you roll a number that you have rolled before. A) for each r=1,2,... calculate the probability pr that you roll exactly r times.

## Homework Equations

## The Attempt at a Solution

p8=p9=...=pinfinity=0

p1=0

p2=1/6

p3=5/18

I think I'm doing this the long way and the wrong way. I know these answers are right because they make sense. But it's getting to hard to count. I need insight on how I should think about this problem. It is basic probability from pitman section 1.6 problem 6. This is not homework. I am just reviewing. Please help! Thanks!