Question

g The first box contains 8 brown balls and 8 yellow balls, the second box contains 4 brown balls and 4 yellow balls, the third box contains 6 brown balls and 2 yellow balls, and the fourth box contains 5 brown balls and 11 yellow balls. The probability of selecting the first box is 0.1, the probability of selecting the second box is 0.2, the probability of selecting the third box is 0.3, and the probability of selecting the fourth box is 0.4. If a ball selected at random from one of the boxes is brown, determine the probability that it was drawn from the second box.

Answer 1

The probability that the selected ball is from the second box (with a probability of 0.2) and (which means multiplication in probability terms) brown (with a probability of 0.5 from same box, having equal number of brown and yellow balls) will be 0.1 ( meaning 0.5 × 0.2)