Multiplication of two numbers is easy, right? At primary school we learn how to do long multiplication like this: Methods similar to this go back thousands of years, at least to the ancient Sumerians ...

The first line of the calculation is the same procedure as multiplying with a single digit number. In the second line we are multiplying by \(20\) (two tens). As we are multiplying by tens the unit's ...

This article reveals a simple and effective shortcut for multiplying numbers that end in 5. Perfect for students, it breaks down the trick for both single-digit and double-digit numbers ending in 5, ...