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प्रश्न
A pair of dice is thrown. What is the probability of getting an even number on the first die or a total of 8?
उत्तर
n(s) = 36
A = {(2,6), (6,2), (3,5), (5,3), (4,4)
(2,1), (2,2), (2,3), (2,4), (2,5)
(4,1), (4,2), (4,3), (4,5), (4,6)
(6,1), (6,3), (6,4), (6,5), (6,6)}
P(A)=`("n"("A"))/("n"("S"))=20/36=10/18=5/9`
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