Answer: 15 gallons
Explanation:
Here you are going to want to set up a proportion. 918 miles per 27 gallons = 510 miles per x gallons
918/27 = 510/x
Cross multiply and you get 918x = 13770
and you get x = 15
Or you could do 918 miles / 27 gallons = 34 miles / gallon
and divide the 510 miles of distance by how many miles per gallon, so
510 / 34
15