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MHT CET202012 Oct 2020Morning ShiftMathematicsProbabilityActual

The probability that a person wins a prize on a lottery ticket is 1 4 . If he purchases 5 lottery tickets at random, then the probability that he wins at least one prize is

Options

  1. A121 1024
  2. B774 1024
  3. C781 1024
  4. D223 1024

Correct answer

C. 781 1024

Step-by-step solution

Var (x)=E (x² )-[E(x)]²0.96=1-[E(x)]² [E(x)]²=1-0.96=0.04 E(x)=0.2

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