I'm having a great discussion with a friend about the following... 1. if x=1.999...infinity, then 10x=19.999...infinity. Subtracting 10x from x gives 9x=18. Dividing both sides results in x=2. 2. Using your calculators on this one. 1/9=0.111...?. 2/9=0.222....?. 3/9=0.333...?. 4,5,6,7,8 follow the same pattern. What, then is 9/9? It is 0.999...infinity. Do you think those are valid? I think they are and thinking in infinite terms 1.999...infinity is equal to 2. My friend thinks he can add any number to infinity because he just can. Food for thought. Any you want to add?