A works 7 hours a day at the rate of 180 per hour. B works 5 hours a day at the rate of 160 per hour. What is the ratio of daily earnings of A and B?

At a construction site, 200 workers were working on a building which is scheduled to end within 250 days. After 30 days, 20 workers leave the job. How many more days will it take to complete the work?