4. The Latin Club chartered a bus to travel to and participate in a state competition. The cost for each adult to ride the bus was $25 and the cost for each student to ride the bus was $15. A total of 17 people rode the bus. The total paid for the bus was $305. Write a system of equations to represent the situation. Then, solve to find the total number of adults and the total number of students. Let a represent the number of adults and s represent the number of students.