Computers too. In fact, let's take technology all the way back before the abacus. Nobody should ever need to reproduce the problem physically, or rely on another system to do it for them, quickly. :P /sarcasm
I think comprehending the problem, and how to describe it as a mathematical formula, is more important. If you can get a naturally spoken problem translated into the language of mathematics, then you understand a great deal more of the important stuff.
If you know what something does, then you can solve it yourself, if necessary. But part of advancing as a species means that we leave some practices of the old world in the past, and move forward. I see no reason to not capitalize on calculators. Imagine how much further ahead our kids could be?