Subject
Quantitative Aptitude
Topic
Probability
A room contains 3 brown, 5 black and 4 white chairs. Two chairs are picked and are put in the lawn. What is the probability that none of the chairs picked is white ?
A room contains 3 brown, 5 black and 4 white chairs. Two chairs are picked and are put in the lawn. What is the probability that none of the chairs picked is white ?
ক)
14/33খ)
14/55গ)
12/55ঘ)
13/33Explanation
Total number of chairs = (3 + 5 + 4) = 12. Let S be the sample space. Then, n(s)= Number of ways of picking 2 chairs out of 12 = 12 × 11/ 2 × 1 = 66 Let n(E) = number of events of selecting 2 chairs for selecting no white chairs. => 8 C 2 = 8 × 7/ 2 × 1 = 28 Therefore required probability = 28/66 = 14/33.Related questions
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