A simple maths trick which allows you to work out your age and shoe size is taking the internet by storm.
Just take your shoe size, multiply it by 5, add 50, multiply that answer by 20, add 1015 and then subtract the year you were born and you should land on your age and shoe size.
Did it work?
There are a few variables, in that the equation won't work if you've already had your birthday in 2016, or you have half a shoe size (instead of 5, multiply your shoe size by 50 instead).