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AP EAMCET202421 May 2024Morning ShiftMathematicsProbabilityActual

7 coins are tossed simultaneously and the number of heads turned up is denoted by the random variable X . If is the mean and ^2 is the variance of X , then ^2 P(X=3) =

Options

  1. A56 5
  2. B84 5
  3. C112 5
  4. D224 5

Correct answer

C. 112 5

Step-by-step solution

aligned & n=7, p= 1 2 , q= 1 2 , =n p= 7 2 & ^2=n p q= 7 4 & p(X=3)= ^7 C ₃ ( 1 2 )^4 ( 1 2 )^3 & ^2 p(X=3) = 7 7 2^7 2 4 ^7 C₃ = 112 5 aligned

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