Answer:
Every 18 miles he uses 3 gallons
divide this:
18 ÷ 3 = 6 miles per gallon
30 miles = 30 ÷ 6 = 5 gallons
7 gallons = 7 x 6 = 42 miles
48 miles = 48 ÷ 6 = 8 gallons
10 gallons = 10 x 6 = 60 miles
Hope this helps :D
