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 ...

Methods similar to this go back thousands of years, at least to the ancient Sumerians and Egyptians. But is this really the best way to multiply two big numbers together? Around 1956, the famous ...

This summer, battle lines were drawn over a simple math problem: 8 ÷ 2(2 + 2) = ? If you divide 8 by 2 first, you get 16, but if you multiply 2 by (2 + 2) first, you get 1. So, which answer is right?

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. It's called the Gelosia method and it uses a crosshatch, or lattice template, to multiply large numbers ...

To multiply decimals by 10, 100, and 1000, use place value labels. Write the digits of the decimal using place value labels. Start with the first non-zero digit. To multiply by 10 move each digit one ...

THIS AIN'T YOUR FATHER'S MATH: Here's a bit of low-tech edtech that might just relieve some of the anxiety around multiplying double and triple digit numbers. The Magical Maths blog reports that the ...

Methods similar to this go back thousands of years, at least to the ancient Sumerians and Egyptians. Around 1956, the famous Soviet mathematician Andrey Kolmogorov conjectured that this is the best ...