Milk cup and water cup

There are two identical cups, one containing milk and the other containing the same volume of water. A spoonful of milk is taken from the milk cup to the Cup, stirred evenly, and then a spoonful is taken from the cup to the milk cup. Ask if there are more water in the milk cup, more milk in the water cup, or the two are the same.

1.The first thought was to use a formula to calculate the correct results.

2.This is actually a way of thinking and a way of thinking. In fact, there are as many milk from the milk cup as less water from the water cup, and less water from the water cup to the milk cup, from the milk cup less milk to the water cup, therefore, there are as many final results as possible.

3.In fact, this problem can be further simplified, that is, if there is only one scoop of water in the cup, and there is only one scoop of milk in the milk cup, the final result should be the same as that of both, in this way, I really want to understand it.