A friend comes to other and says can u do me a
favour pick letters randomly from the stack such that
all the letters that u pick are 5% of the total
letters. The other friend while sorting just picked up
letter number one, missed one, picked up another
letter, missed two picked one letter ,missed three,
picked another letter, and so on...till he picked last
letter to his amazement he found that the picked up
letters were 5% of the total letters in the stack. How
many letters did he pick?