This needs to be solved using Bayes Formula/Theorem. I get stuck finding R2/R1

Urn 1 contains 4 red and 6 white balls. Um 2 contains 6 red and 3 white balls. A ball is drawn from urn 1 and placed in urn 2. Then a ball is drawn from urn 2. If the ball drawn from um 2 is red, what is the probability that the ball drawn from um 1 was red? The probability is (Type an integer or decimal rounded to three decimal places as needed.)