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A bag contains 5 blacks balls and 3 red balls. Two balls are picked at…

A bag contains 5 blacks balls and 3 red balls. Two balls are picked at random without replacement. What is the probability that a black and red balls are picked?
  • A.
    15/28
  • B.
    13/28
  • C.
    5/14
  • D.
    3/14
Correct Answer: Option A
Explanation

Black balls = 5
Red balls = 3/8
P(B) = 5/8, P(R) = 3/8
P( a Black and a Red) = BR + RB
= (5/8) * (3/7) * (3/8) * (5/7)
= (15/56) + (15/56)
= 30/56
= 15/28