How many trees do you need?
The women use logic: 10 m divided by 1 m is 10, plus one tree either for beginning or end, the correct result is 11 trees.
The men do not think at all, they play (either in their head or by using a piece of paper):
make one dot for the first tree, then go 1 square on the paper forward, second dot, and so on, in the end, they count the dot, correct result is: 11 trees.