What we know: During the rebuilding, after WWII, we were short of tractors. The machine and tractor stationd would lend each other equipment as needed. Three machine and tractor stations were neighbors. The first lent the second and third as many tractors as they each already had. A few months later, the second lent the first and third as many as they each had. Still later, the third lent the first and second as many as they each already had. Each staion now had 24 tractors.
Enigma: How many tractors did each station have originally?
Solution: You can solve the problem easily backward
First+Second+Third
24 + 24 + 24 = 72
12 + 12 + 48 = 72
6 + 42 + 24 = 72
39 + 21 + 12 = 72
The first had 39 tractors, the second had 21 and the third had 12.
