Akeem fills the tank of his car with gasoline. He completes the table below to show the distance he travels and the amount of gasoline left in the tank.

Distance Traveled and Gas Left in Tank
Distance Traveled
(in miles)
0
20
60
100
?
Amount of Gas Left in Tank
(in gallons)
12
11
9
7
0

Which problem can Akeem solve when he completes the table?