A bag contains 3 red, 4 white and 5 blue balls. All balls are different two balls are drawn at random. the probability that they are of different colour is a. 47/66            b. 10/33            c. 1/3          d. 1

Explanation

Total number of bassl `=3+4+5=12`


Favourable number of cases are total minus the balls drawn from same colour


`12​_(C_2)​−(3_(​C_2)​+4​_(C_2)​+5_(​C_2)​)`


`=66−(3+6+10)=66−19=47`


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