I have another problem i cound't figure how to start.

problem:

Jack and Jill spent two weeks (14 nights) touring boston, new york city, philadelphia, and washington d.c. they paid $120, $200, $80, and $100 per night respectively. their total bill was $2020. the number of days spend in NYC was the same as the total number days spent in boston and d.c. They spent 3 nights as many days in NYC as they did in philly. How many days did they stay in each city?

please help. thanks!