About 31.5% when rounded.
This is because you have to start with the probability of each urn. The first urn has 13 total balls (5 white and 8 yellow). Since 5 of them are white, the odds of pulling a white ball are 5/13. Then find the same for the second urn (9 white and 2 yellow). Therefore there are 11 total balls and 9/11 chance of getting a white one. After finding both, multiply them together to get the answer.
[tex] \frac{5}{13} [/tex]*[tex] \frac{9}{11} [/tex]= [tex] \frac{45}{143} [/tex]= 31.5%
