In the middle of the desert you have a fuel depot and some jeeps each of which can travel 100 miles on a tank of fuel. The usual problem is to find out how far away from base it is possible to explore which involves building up intermediate fuel dumps in jerry cans. In this version however this is impossible (perhaps there are no jerry cans) and the only way a jeep can get extra fuel away from base is to transfer some from the tank of another.
If two jeeps go out together after 33.33 miles each will have used 1/3rd of a tank, the support jeep transfers 1/3rd to the scout jeep, returns to base, where it refuels and returns to the same point to wait for the scout jeep to return. It can then give it enough fuel for both to get back to base. This gives two jeeps a range of 33.33 + 50 = 83.333 miles.
What is the range for N jeeps for N = 3 to 7?
If fuel dumps are possible, there is an equation to calculate the range, but I don't think this is true for this version.
I tackled this problem many years ago and can't remember the answers I got so don't expect me to be able to confirm any results!