I had this problem on a test, and it was only an alteration of a problem i had on a homework. But for some reason, if i use the same method to figure it, i get the wrong answer. I know the answer is 2/3 but i don't know the steps to solve it.
My problem is how, >.< i can't figure it out. If it was positive infinity i would multiply by 1 or 10^-x/10^-x and get -1, but that doesn't seem to work. What am i missing?