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MHT CET202411 May 2024Morning ShiftMathematicsProbabilityActual

If three fair coins are tossed, then variance of number of heads obtained, is

Options

  1. A0.25
  2. B3
  3. C0.75
  4. D1.5

Correct answer

C. 0.75

Step-by-step solution

Let r.v X denotes the no. of heads obtained Probability distribution of X is given as aligned E (x) & =0 1 8 +1 3 8 +2 3 8 +3 1 8 = 3 2 E (x^2 ) & =0 1 8 +1 3 8 +4 3 8 +9 1 8 =3 ~V (x) & = E (x^2 )-[ E (x)]^2 & =3- 9 4 & = 3 4 & =0.75 aligned

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