Please solve #12, it is about linear verbals

The scale for a map is 20 miles = 1/2 inch. the distance between two towns on the map is 3 3/4 inches. what is the actual distance between these towns? 150 miles 38 miles 75 miles 135 miles

Can someone me out here and the tell me the greatest common factor

10% of 1,900,000. show me how you got the answer