This is the problem that I am stuck on:
My error message:
Oops, try again. trip_cost('Charlotte', 9) raised an error: unsupported operand type(s) for -: 'str' and 'int'
My code: def plane_ride_cost(city): if city == "Charlotte": return 183 elif city == "Tampa": return 220 elif city == "Pittsburgh": return 222 elif city == "Los Angeles": return 475 def rental_car_cost(days): cost = 40*days if days >= 7: return cost-50 elif days >= 3: return cost-20 return cost def hotel_cost(days): return 140*days def trip_cost(days,city): sum = rental_car_cost(days) + hotel_cost(days) + plane_ride_cost(city) print sum return sum