A weekend puzzle
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?