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MHT CET202211 Aug 2022Morning ShiftMathematicsProbabilityActual

If the p.m.f. of a discrete random variable X is P(X=x)= c x^3 , x=1,2,3=0 , otherwise then E(X) is equal to

Options

  1. A297 294
  2. B249 225
  3. C343 297
  4. D294 251

Correct answer

D. 294 251

Step-by-step solution

aligned & P_i=1 & 251 216 C & C= 216 251 & now E(x)= p_i x_i= 49 36 C= 49 36 216 251 = 294 251 aligned

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