Math train

Question: You are the conductor of a train... And at your first stop 5 people walk in, At your next stop 2 people walk out, and 12 walk in, at your next stop 6 walk in and 4 walk out, at your next stop 12 people walk out and 9 people walk in, at your next stop 3 people walk in, and 1 person walks out. Who is the train conductor?

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