Maths A-Level again im so badWatch
I have a pack of playing cards, numbered 1-52. They are in order with 1 on the top and 52 on the bottom. I go through the pack discarding every other card, so I end up with a new pile which has 1 on top, then 3, 5, 7.... up to 51. I do the same with the new pile, and so on, getting even smaller piles.
NOTE: If the last card in the pile is one i keep, I will discard the top card of the subsequent pile.
What is the last card i'm left with?
What if i do it again, but discard the 1, keep the 2m etc...?
What if i start with 100 cards?