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MHT CET202020 Oct 2020Evening ShiftMathematicsProbabilityActual

It is known that a box of 8 batteries contains 3 defective pieces and a person randomly selects two batteries from the box. If X is the number of defective batteries selected, then P(X 1)=

Options

  1. A25 28
  2. B14 28
  3. C10 28
  4. D13 28

Correct answer

A. 25 28

Step-by-step solution

We have probability of selecting defective batteries = 3 8 aligned & p= 3 8 and q= 5 8 & P(X=0)+P(X=1) &= [ 2 0 ( 3 8 )⁰ ( 5 8 )² ]+ [ 2 1 ( 3 8 )¹ ( 5 8 )¹ ] &= 25 64 + 2 3 5 64 = 55 64 aligned

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