The percentage swap

Hello, and welcome to Myriora Maths! What is eight percent of fifty? It sounds tricky. But there's a swap that makes it easy!

Here's the trick. Eight percent of fifty is the same as fifty percent of eight. And fifty percent is just half. Half of eight is four. So eight percent of fifty is four!

Why does the swap work? Percent means out of one hundred. So eight percent of fifty is eight, times fifty, divided by one hundred. And fifty percent of eight is fifty, times eight, divided by one hundred. Eight times fifty is the same as fifty times eight. So the answers are the same!

Let's try some more. Four percent of twenty-five? Swap it: twenty-five percent of four, which is a quarter of four. That's one! Eighteen percent of fifty? Swap it: fifty percent of eighteen, which is nine!

When should you swap? When the second number is a friendly percentage, like fifty, twenty-five, twenty or ten. Twelve percent of ten? Swap it: ten percent of twelve. That's one point two!

A common mistake is forgetting that percent means out of one hundred. Eight percent of fifty is not four hundred! That's just eight times fifty. Divide by one hundred, and it's four.

Your turn! What is sixteen percent of twenty-five? You've got twenty seconds, or pause the video if you need more time. Go!

Time's up! Swap it: twenty-five percent of sixteen. A quarter of sixteen is four!

Quick review. You can swap the two numbers in a percentage question. Pick the order that's easier. Fifty percent is a half, twenty-five percent is a quarter, and ten percent is a tenth. See you next time!