29. 3 red marbles, 4 blue marbles and 5 green marbles are distributed to 12 students. Each student gets one and only one marble. In how many ways can the marbles be distributed so that Jamy and Jaren get the same colour and Jason gets a green marble?
29. Answer: 3150 .
Case 1: Jamy and Jaren both take red marbles. So 1 red, 4 blue and 4 green marbles are distributed to 9 students:
$$
\binom{9}{1} \times\binom{ 8}{4}=630 .
$$

Case 2: Jamy and Jaren both take blue marbles. So 3 red, 2 blue and 4 green marbles are distributed to 9 students:
$$
\binom{9}{3} \times\binom{ 6}{2}=1260 .
$$

Case 3: Jamy and Jaren both take green marbles. So 3 red, 4 blue and 2 green marbles are distributed to 9 students. The number is the same as case 2 .
$$
630+1260+1260=3150 .
$$