**A** and **B**) and on the both trees are some birds.

The **birds of tree A** say to the **birds of tree B** that if one of you comes to our tree, then our population will be the **double** of yours.

Then the **birds of tree B** tell to the **birds of tree A** that if one of you comes here, then our population will be **equal** to that of yours.

Now answer: How many birds on each tree**?**

This problem is a part of the set brain games