Three balls are drawn at random without replacement what is the probability that first ball is black second ball is black and third ball is white
I got two answer and confused which one is right or no one is right
first is we can select first two black balls by 10C2 ways and white balls by 20 ways so total no of ways of selecting an event is 10C2*20. And total no of ways to select 3 balls is 30C3. ans is 10C2*20/30C3.
and second approach was to select one black ball the prob is 10/30 followed by to select another black ball the prob is 9/29 and to select white ball is 20/28 Ans is 10*9*20/30*29*28