Comic Book Math

Tonight while I was at Border's with my friend Tammy, her son Noah was reading DC Comic Books. He found a riddle in one of them and tried it on me.

Here's the set-up. The supervillian Felix Faust tries to lead the readers to believe he can read their minds. He says the following:

"Choose a number between 1 and 50, but don't tell me what it is.
Add 8 to it,
then subtract 5,
then add 7,
then subtract 6,
and then subtract your original number from that result."

He is then able to tell you what number you get as your answer, even though he didn't know what number you started with!! Yikes! Should you fear the mind-reading powers of this supervillian?





But then one of the superheros from the Justice League of America pops up and reassures the reader that supervillian Felix Faust is not really mind reading but that it is just a trick and encourages the reader to try it on friends to see that it works every time.

What number did Felix Faust say you came up with?

Does it work every time?

Would it work for numbers bigger than 50?