Two balls are drawn at random with replacement from a box containing 10 black and 8 red balls. Find the probability that one of them is black and other is red.

Two balls are drawn at random with replacement from a box containing 10 black and 8 red balls. Find the probability that first ball is black and second is red.

Two balls are drawn at random with replacement from a box containing 10 black and 8 red balls. Find the probability that both balls are red.

A bag contains 10 white, 6 black and 4 red balls. Find the probability of getting : a black ball

Bag I contains 4 red and 5 black balls and bag II contains 3 red and 4 blacks balls. One ball is transferred from bag I to bag II and then two balls are drawn at random (without replacement) from bag II. The balls so drawn are both found to be black. Find the probability that the transferred ball is black.