a)
Solution,
According to fuel gauge,the petrol left is exactly between 1/2 and 3/4 part of the 40 litres.
i.e. Left fuel = (1/2 + 3/4)/2 litres
Here,
1/2 of 40l = 1/2×40l
= 20l
3/4 of 40l = 3/4×40l
= 30l
Then,
Left fuel = (20l + 30l)/2
= 50l/2
= 25l
Consumed fuel = 40l - 25l
= 15l
Therefore,15 litres of petrol is used to travel 240km
b)
Solution,
Consumed fuel = 15l
Distance covered = 240km
Then,
Fuel consumption rate = 240km/15 l
= 16km/l
Therefore,the rate of petrol consumption is 16km/l of his car for this journey