A shipment of 8 television sets contains 2 black-and-white sets and 6color sets. If 2 television sets are to be chosen at random from this shipment, what is the probability that at least 1 of the 2 sets chosen will be a black-and-white set?
A. 1/7 B. ¼ C. 5/14 D. 11/28 E. 13/26
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set24-Q.4--B&W,Colour TV
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prachich1987
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Rahul@gurome
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Required probability is = 1 - (probability that both sets are color sets).
Probability that both are color sets is 6C2/8C2 = 30/56 = 15/28.
So correct answer is 1 - 15/28 = 13/28.
Probability that both are color sets is 6C2/8C2 = 30/56 = 15/28.
So correct answer is 1 - 15/28 = 13/28.
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Scott@TargetTestPrep
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We can use the formula:prachich1987 wrote:A shipment of 8 television sets contains 2 black-and-white sets and 6color sets. If 2 television sets are to be chosen at random from this shipment, what is the probability that at least 1 of the 2 sets chosen will be a black-and-white set?
A. 1/7 B. ¼ C. 5/14 D. 11/28 E. 13/26
P(at least one black and white TV) = 1 - P(No black and white TV)
P(No black and white TV) = 6/8 x 5/7 = 3/4 x 5/7 = 15/28
P(at least one black and white TV) = 1 - 15/28 = 13/28
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