Answer:
50 litres
Explanation:
If you think of it as a ratio, there are 20 litres to every 160 km. There are __ litres to every 400 km. To get to 400, 160 is multiplied by 2.5
So multiply 20 by the same number and you get the number of litres for 400 km.
20 * 2.5 = 50