Question 473247
There are 6+3 = 9 balls total.



P(3 red) = P(red)*P(red)*P(red)



P(3 red) = (6/9)*(5/8)*(4/7) .... Note: I'm assuming that the balls are NOT replaced (or put back in)



P(3 red) = 120/504



P(3 red) = 5/21