Moltiplicatore in colonna

Multiplies as they used a time when there was no calculator, that is, as if it were with the pen on a sheet of squared; putting the multiplicand on the first line followed by X, then the multiplier on the second line followed by =; pulling a horizontal line and then multiplying one digit at a time and summing. Multiply also decimal numbers, but the multiplier must not have more than three digits.
The same column system is used to divide two numbers, even decimal.
And the square root?
That complicated and full of errors?
E 'right now is done with this application quickly.
Useful for checking math homework.