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AP EAMCET202017 Sep 2020Morning ShiftMathematicsProbabilityActual

Let (X ) be a random variable such that (X(x) ) is the number of heads in (X ) for each (x S ), where (S ) is the sample space of random experiment of tossing three fair coins simultaneously. Find the value of ( (X⁻¹(2) ) ).

Options

  1. A( 3 8 )
  2. B( 5 8 )
  3. C( 1 8 )
  4. D( 3 4 )

Correct answer

A. ( 3 8 )

Step-by-step solution

Tossing of three coins So, ( (X⁻¹(2) ) ) means probability of getting two tails when three coins are tossed. ( (X⁻¹(2) )= 3 8 )

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