Finding Hours Worked by Alex in Joint Work

In a small town, two local painters, Alex and Jamie, are hired to paint houses. Alex charges $50 for the first hour and $30 for each additional hour. Jamie charges a flat fee of $70 for the first hour and $20 for each subsequent hour. Both painters were hired to work together on a particular house, which took them a total of 5 hours to complete. If the total amount charged by both painters was $250, determine how many hours Alex worked on this job.