Answer:
63 liters
Explanation:
The amount of fuel used per day is ...
... (1 tank - 2/3 tank)/(6 days) = (1/3 tank)/(6 days) = (1/18) tank/day
Then the amount of fuel used after 6+11 = 17 days is
... (17 days)×(1/18 tank/day) = 17/18 tank
and the amount remaining is ...
... (1 tank -17/18 tank) = 1/18 tank = 3 1/2 liters
To find the tank size, we can multiply this result by 18:
... 1 tank = 18×(3 1/2 liters) = 63 liters
