So the purpose of the question is to find how many liters of fuel per 100km.
There are 2 ways
Either by cross multiplication or by directly calculating it
• By cross multiplication:
340km -----> 255 liters
100km -----> x liters
So 340x = 100(255)
x= 25500/340
x= 75 liters is the amount of liters of fuel used by the car every 100km.
• By directly calculating it:
Basically since it's every 100km, you're similarly finding the percentage, so:
(255 liters/ 340km) x 100km = 0.75 x 100 = 75 liters is the amount used by the car every 100km.