Please explain how to answer.
A box has 6 red hats and 5 green hats. What is the probability of drawing at least one green hat in two consecutive drawings if the hat is not replaced?
a) 10/11
b) 8/11
c) 7/12
d) 5/13
e) 2/7
probability hats
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jzebra10 wrote:Please explain how to answer.
A box has 6 red hats and 5 green hats. What is the probability of drawing at least one green hat in two consecutive drawings if the hat is not replaced?
a) 10/11
b) 8/11
c) 7/12
d) 5/13
e) 2/7
Probability of drawing at least one green hat in 2 consecutive drawings = 1 - probability that both the hats are red
Now, probability that both hats are red = 6/11 * 5/10 = 3/11 (since there is no replacement)
Therefore, required probability = 1 - 3/11 = [spoiler]8/11[/spoiler]
The correct answer is B.
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