only 0.99999999999... with an infinite number of 9s = 1..... but this is a finished number we are talking about. 99.99999999999999999999999999999999999999999999999999999999999999999999 is not = to 100, however if we are talking about an infinitely precise number, (ie: infinite number of 9s after the decimal, only then is it = 1 to

in this case it would be 100^- not 100. It is entirely possible, though not very likely, that someone who mines at a difficulty of 1, with 100 Thash, doesn't find a block in a hundred years. I'd hate to be that guy though lol