Generations of students have spent many math lessons with written multiplication. That does not have much to do with mathematics - more about that here. But there are moments when it is quite helpful to not only type in the calculator, but actually can still count in writing. As with the following task.
A three-digit number is multiplied by a two-digit number. The calculation is on a blackboard. But most of the digits are blurred and unrecognizable. Only the number 1 appears four times - see picture above.
What was the original bill? Can it be reconstructed clearly?
