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AP EAMCET20226 Jul 2022Evening ShiftMathematicsProbabilityActual

A discrete random variable X has the distribution B(15, p) . Given that Var (X)=3.15 . Then, the two possible values of p are

Options

  1. A0,1
  2. B0.1,0.9
  3. C0.4,0.6
  4. D0.3,0.7

Correct answer

D. 0.3,0.7

Step-by-step solution

aligned & Here, n=15, q=1-p & Var (X)=315 ; n p q=315 & 15 p(1-p)=315 & p-p^2=0.21 p^2-p+0.21=0 & p^2-0.7 p-0.3 p+0.21=0 & p(p-0.7)-0.3(p-0.7)=0 & p=0.7,0.3 aligned

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