Two hats are picked at random, what is the probability that all hats are of green colour?
Total number of hats = 6 + 4 + 2 + 4 = 16 Let S be the sample space. Then, n(S) = number of ways of drawing 2 hats out of 16 = ¹⁶C_₂ = (16 × 15)/( 2 × 1) = 120 Let E= event of drawing all the hats are of green colour n(E) = ²C_₂ = 1 ∴ P (E) = (n(E))/(n(S)) = 1/120
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