Introducing the maths trick that's breaking the internet.

It turns out that a simple maths formula can predict your age and shoe size – and its freaking out the entire internet.

Want to play? Here’s how. Calculators at the ready…

Simply take your shoe size (mine’s 8), multiply it by 5, and add 50.

Now multiply your answer by 20, add 1015 and then subtract the year you were born (in my case,1986).

And voila.

Mind blown. Who said you would never do maths again after leaving school?

For those of us (ie me) who did not excel at maths at school, the trick seems more magic than logic.

But maths boffins assure us it is not as bamboozling as it first appears (sorry to ruin the fun).

Australian Mathematical Sciences Institute director Geoff Prince told that there was a simple explanantion.

“It’s actually a formula, and the 1015 is a real giveaway to how the answer is resolved,” he said.

“The cleverness is making sure the shoe size is multiplied by a big enough number that it comes first in the final answer.

“The way the formula was constructed kind of hides everything, and it really is quite easy to make these kinds of equations up.”

Whatever. It still seems like magic to us. Whatever those clever boffins have to say.

 Were you good at maths at school?