<human>:  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?
<bot>: How many people are on the second bus? ** The second bus is carrying 12 * 2 = <<12*2=24>>24 people.
How many people are on the third bus? ** The third bus has 24 – 6 = <<24-6=18>>18 people.
How many people are on the fourth bus? ** The fourth bus has 12 + 9 = <<12+9=21>>21 people on it.
How many people are going to the museum in total? ** In total, there are 12 + 24 + 18 + 21 = <<12+24+18+21=75>>75 people on the buses.
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