A bag contains 6 black and 8 red balls. A ball is drawn at random from the bag. If the ball drawn is

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05 Jan 2010 red and black ball

A bag contains 6 black and 8 red balls. A ball is drawn at random from the bag. If the ball drawn is black, a coin is tossed twice otherwise no coin is tossed. What is the probability to get two heads respectively on the coins.

OPtion

1) 1/8
2) 1/4
3) 3/7
4) 1/7
5) 3/28
6) 3/14
7) 2/7
8) 1/2
9) 1/3
10) 1/48

Solution

Probability of drawing a black ball is 6/14 = 3/7
After then the probability of getting two successive heads is 1/2 * 1/2 = 1/4
Net probability = 3/7 * 1/4 = 3/28

Correct Option: 5 Best Solution (2)