Probability

⭐ Important Questions

1. Two cards drawn without replacement from 52 cards. Find P(both aces).
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   P = 452 x 351 = 122652 = 1221
2. A random variable X has P(0)=0.2, P(1)=0.3, P(2)=0.4, P(3)=0.1. Find mean and variance.
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   Mean μ = 0(0.2)+1(0.3)+2(0.4)+3(0.1) = 1.4\nE(X²) = 0+1(0.3)+4(0.4)+9(0.1) = 2.8\nVar = E(X²) - μ^2 = 2.8 - 1.96 = 0.84