Rolling along math problem?

[meghansavageisontheroll]

Three busloads of students drove off on a field trip.

1. fiftey students rode the first bus. The ratio of boys to girls on this bus was 2:3.
2. The ratio of boys on the first bus to boys on the second bus was 5:6, though the ration of girls to boys on bus 2 was 50:50.
3. The ratio of girls on the 3rd bus to girls on the 2nd bus was 7:8.
4. Boys comprised 40% of the students on the third bus.

What is the total number of students aboard the 3 buses?
if you can solve this..THANKYOU!
please show how you got the answer.