We have 3 white balls in the first urn out of 9. That means we have a 1 in 3 chance at picking the white ball in the first urn.
Now, we have a 3 in 11 chance at picking the white ball in the second urn.
Since, we want them simultaneously, we need to multiply them.
1/3 × 3/11 = 1/11 chance
