Q-30
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P(blue and green)= P(1st is blue and 2nd is green OR 1st is green and 2nd is blue)engg.manik wrote:30.There are 10 marble balls, including 5 green, 3 blue, and 2 red, in a container. One ball is picked out then put back, then another ball is selected. What is the probability that a green ball and a blue ball will be selected?
= P(1st is blue and 2nd is green) + P(1st is green and 2nd is blue)
= (3/10)(5/10) + (3/10)(5/10)
= 3/10