19 is only 1 away from 20, so you prefer to start by multiplying 20 times 5, which equals 100. Then we need to take away a squadron of 5, because there are actually only 19 squadrons, not 20. 100 take ...

Napier’s method of multiplication is a method used to multiply large numbers when you do not have a calculator. Draw a 2 by 2 grid to multiply a 2-digit number by another 2-digit number. Label the ...

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, ...