Answer:
Distance between the cities on the map = 101, 000 miles
Explanations
According to the question :

Therefore, 1 inch = 2020 miles.
This means that 1 inch represents 2020 miles
The distance between the two cities = 50 inches
Since 1 inch = 2020 miles
50 inches will represent (50 x 2020) miles = 101,000 miles
The distance between the two cities on the map = 101, 000 miles