Ok so the answer is 5 adults. The total cost of the trip is $591 and the cost of hiring the coach was $118. So now what you did is that you subtract $591-$118=$473. For entrance fee was $8.75 per each child and there was a total of 47 children. Then multiply 47x8.75 and you get $411.25. And then subtract 473 by 411.25 and which will be 61.75. And then the cost of each adult is $12.35. Then you divide 61.75 by 12.35. Then when you divide it and the answer should be 5. Which means that the amount of adults inside the group was 5. Hope this helps!