Q8 of 64 Page 122

A bag contains 5 black and 6 red balls. Determine the number of ways in which 2 black and 3 red balls can be selected from the lot.

Formula: -(i)nCr


Given: -Number of black ball =5,Number of red ball =6


Number of ways of selection of 2 black balls


=5C2


Number of ways of selection of 3 red balls


=5C3


Number of ways of selection of 2 black & 3 red ball


=5C2x5C3


=10×20


=200


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