Question

(a) Suppose a Toy factory makes 4,000 are Blue and rest are Black. You es 20,000 toys on a day. Out of which 10,000 are Red, o ility that the teot tre Black. You begin picking Toys in random, whiat is the probability that the 10th toy you pick will be the third Black toy

Answer 1

P(Black toy) = (20000 - 10000 - 4000)/20000 = 0.30

Hence,

P(3rd black in 10th toy)

= P(2 blacks in 9 toys)*P(3rd black in 10th toy)

$= (\binom{9}{2}(0.30)^2(0.70)^7)*(0.30)$

= 0.08005