On Friday I posted this puzzle….
Imagine that there are 2 trees in a garden. Let us call them Tree A and Tree B. Now imagine that there some birds on both trees.
The birds on Tree A say to the birds on Tree B: ‘If one of you comes to our tree, then our population will be the double of yours.’
Then birds on Tree B say to the birds on Tree A: ‘If one of you comes to our tree, then our population will be equal to that of yours.’
How many birds are there in each tree?
If you have not tried to solve it, have a go now. For everyone else the answer is after the break.
There are 7 birds on Tree A, and 5 on Tree B. Did you solve it?
I have produced an ebook containing 101 of the previous Friday Puzzles! It is called PUZZLED and is available for the Kindle(UK here and USA here) and on the iBookstore (UK here in the USA here). You can try 101 of the puzzles for free here.