Bill Hubbard, what can I say – 3 different airlines, 6 flights, 4 different cities this week. You know who to blame for one more puzzle 🙂

Anybody who works out the answer, feel free to post the answer only in the Comment section. Send your logic as a personal message to me. Do not write your logic in the Comments section.

Now to the puzzle.

In a Polynesian island, girls are highly preferred as a child. This has led to a strange practice over the years among couples who are trying to have a baby. If they have a baby boy, they keep trying to have another baby in the hope that it will be a girl. If it is a baby girl though, they stop having any more babies. Of course, given any birth, the probability of having a baby boy or baby girl is half and half. So, they keep having more babies as long as they are all boys and stop moment they have a girl

As a result, there are couples who have one girl, couples who have one boy and one girl, couples who have two boys and one girl, couples who have three boys and one girl (and the girl is always the last baby they have) but no couple with two girls (or more).

Here is the question: Over a longer period of time, what is the likely ratio of boys and girls in the island?

In a class there were 40 students with roll numbers 1 thru 40. One day, the teacher got them all to sit around in a circle sequentially in the order of their roll numbers (1 thru 40). (Of course 40 sat next to 39 on one side and 1 on the other). She then gave a wand to student number 1. What the student had to do is turn towards the next student (which would be #2) and tag him/her with the wand. Upon tagging, the tagged student steps back and is out of the game and the wand is then handed to the next student – which would be student #3 in this case

Now student #3 does the same thing – tags student #4 who steps back and is out of the game and then the wand is handed to #5.

This keeps going on and on (in circles) till only one student is left.

Can you figure out which student was the last one left?