This is profit and loss problem; The formula is: 1, and when there is profit and loss: (profit+loss) ÷ the difference between the two distribution schemes = the amount after each word.

(Profit and loss) The difference between the two distribution schemes = the amount after each word.

2. Double profit time: (big profit-small profit) ÷ The difference between the two distribution schemes = the amount after each word.

3. Double loss: (big loss-small loss) The difference between the two distribution schemes = the amount after each word.

This problem belongs to both interests. The formula is: (14-4)÷(7-5)=5 (room)

5×5+ 14=39 (person) or 5×7+4=39 (person)