LOL, yeah.... I remember somebody watching over my shoulder when I was writing code, and suddenly he said "Looks like mathematics" and I replied "Well, it is", and suddenly he didn't like coding anymore....
Well, decimals are rational numbers and rational numbers are countable. You'd never finish but technically you could do it. But there's also an infinite amount of irrational numbers between any two rational numbers and those you just can't count - not even with an infinite amount of time...