A bag contains 3 red and 5 black balls and second bag contains 6 red and 4 black balls. A ball is drawn from each bag. Find the probability that one is red and the other is black.

Explanation

We have:


Bag `1=(3 R+5 B)` balls


Bag` 2=(6 R+4 B)` balls


P( 1 is red and 1 is black )=P( red from bag 1 and black from bag 2)+P( red from bag 2 and black from bag 1 )



`=frac{3}{8} times frac{4}{10}+frac{5}{8} times frac{6}{10} `

`
=frac{12}{80}+frac{30}{80} `

`
=frac{42}{80} `

`
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