If 2 pens are drawn at random what is the probability that none of them is blue?
Let S be the sample space. Then, N(S) = number of ways of drawing 2 pens out of 11 = ¹¹C₂ = (11 ×10 )/(2 ×1) = 55 Let E = event of getting none of them is blue. n(E) = ⁸C₂ = (8 ×7 )/(2 ×1) = 28 n(P) = (n(E))/(n(S)) = 28/55
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