Suppose there are two identical cups of water. One is red, the other is green. You take out 1ml of red water and put it into the green water. Th

Suppose there are two identical cups of water. One is red, the other is
green. You take out 1ml of red water and put it into the green water.
Then you take 1ml of (mixed) green water into the red water. Does the
red water have more green or does the green have more red?

Red Green
X X
Red: x-1 red: 1, green x
Red: x-1+1/(1+x) green: x/(1+x) red: 1-1/(x+1) green: x-x/(x+1)
So they are equal