I agree that probably training too much manual addition and multiplication is a waste of time these days. However, a bit of it still seems to be useful. For exa

I agree that probably training too much manual addition and multiplication is a waste of time these days. However, a bit of it still seems to be useful. For example I am often able to calculate the bill in a restaurant (not always, though). And sometimes it is just faster than going to the calculator, depending on the situation. Also a lot of the process of addition and multiplication might also be good practice for arithmetics?