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AP EAMCET202017 Sep 2020Evening ShiftMathematicsProbabilityActual

Suppose (A, B ) be two events such that (P(A)=0.9 ) and (P(B)=0.8 ) and (P(A B) 0.7 ). Then, we can conclude that such a case is ____

Options

  1. AAlways true
  2. BAlways false
  3. CNot true in some examples
  4. DTrue only in some cases

Correct answer

A. Always true

Step-by-step solution

Maximum value of probability of (A ) or (B ) is, ( aligned P(A B) & =P(A)+P(B)-P(A B) & =0.9+0.8-0.7=1 aligned ) Which is probability of a sure event. As all other values of (P(A B) ) are less than 1 , so this is always true.

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