I have a question, im asked to solve the following Problem:

An urn contains 6 red balls and 3 blue balls. One ball is selected at random and is replaced by a ball of the other color.

A second ball is then chosen.

What is the conditional probability that the first ball selected is red, given that the second ball was red?

I know that with conditional probabilities the sequential order does not matter in a sense that it does not matter that the second draw has not happened befor the first draw.

But i have no idea how to solve it.

Many thanks for your help