Okay so he spent 54 dollars. Well it says 3/6 of the tickets were children's, and 3/6 is half of it. You find the half, which is 3, and you then multiply it by 8 (because it is the prince). So from there (3*8) you get 24 and you subtract that from 54 (54-24). That should be 30. You only have 3 adult tickets so you should divide the 30 between the adults (30/3). That should equal to adult tickets to being 10 dollars each.
