The probability of drawing is 4/10 = 2/5;
The probability of b drawing is:
1, the situation of a drawing: (2/5)*(3/9)=2/ 15.
2. If A is not drawn: (3/5)*(4/9)=4/ 15.
Then the probability of B being drawn is (2/15)+(4/15) = 6/15 = 2/5;
The probability of c drawing is:
1, and the drawing of both parties: (2/5)*(3/9)*(2/8)= 1/30.
2. Both parties failed to draw: (3/5)*(5/9)*(4/8)= 1/6.
3.A draws B but fails to draw B: (2/5) * (6/9) * (3/8) =110.
4. The situation that A failed to draw B: (3/5) * (4/9) * (3/8) =110.
Then the probability of C winning is (1/30)+(1/6)+(110)+(110) =12.
That is to say, the probability of three people drawing a difficult ticket is 2/5, which proves this point.