The school is organizing a trip to the museum. 4 buses were hired to take the children and teachers to their destination. The second bus has twice the number of people on it as the first bus. The third bus has 6 fewer people than the second bus. The fourth bus has 9 more people than the first bus. If the first bus has 12 people, how many people are going to the museum in total?
The second bus is carrying 12 * 2 = <<12*2=24>>24 people.
The third bus has 24 – 6 = <<24-6=18>>18 people.
The fourth bus has 12 + 9 = <<12+9=21>>21 people on it.
In total, there are 12 + 24 + 18 + 21 = <<12+24+18+21=75>>75 people on the buses.
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