Probability is one of my favs.a) I hope u know smoething about combinations: nCri_ 4C0 * 5C3 )/9C3Which means we are selecting none (0) balls out of four red balls and we are selecting 3 out of 5 blue balls.... The total probability will remain the same because we are slecting 3 random balls out of 9 given balls.ii_ 4C1*5C2)/9C3..iii_ 4C2*5C1)/9C3iv _ 4C3*5C0)/9C3b: Now 3 balls are chosen and one of them is known to be red. So basically u now have to estimate the probability of selecting 2 red balls from 8 coloured balls because 1 ball is chosen and is known to be red. which will as in previous cases be of course 3C2*5C0)/ 8C2Hope it wz some helpTW K
