A stairway has 100 steps. You can climb it by one step at a time, or by two steps. How many different ways to ascend this stairway exist?
(In reply to re: 2 answers
by John zadeh)
Nevermind, the way to solve it is realized that it is only possible to take 1 step an even number of times (or not to take 1 step at all)
The solution is 100C0 + 100C2 + 100C4 + 100C6.......100C100