A bag contains eight green marbles and four blue marbles. what is the probability of drawing a green marble on the second draw?

1 answer:

3 0

<span>2/3 probability of drawing a green marble on the second draw. If the marbles are replaced after each draw, the probability will always be 2/3 of a green marble being drawn. But for this problem, going to assume that the marbles are not replaced after each draw. So we have 2 possible scenarios. 1. The first marble drawn is green This even happens with probability of 2/3 and leaves you with 7 green marbles and 4 blue marbles. So the probability of picking a green marble again is 7/11. 2. The first marble drawn is blue This event happens with probability of 1/3 and leaves you with 8 green marbles and 3 blue marbles. So the probability of picking a green marble this time is 8/11 The total probability of picking a green marble on the 2nd pick is the sum of the product of each probability. So 2/3 * 7/11 + 1/3 * 8/11 = 14/33 + 8/33 = 22/33 = 2/3</span>

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Option D.

Step-by-step explanation:

Suppose that we have a set of N values:

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Because the mean is computed as the sum of the numbers divided by N, and the mean does not change, and N does not change, then the sum of the numbers does not change.

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