Alexis Lemaire holds the world record for mental arithmetic. He is able to perform the cubed root of a one hundred-figure number in just 13 seconds!
Give your brain a gentle workout, with "CalQ", a maths-based puzzle game. The aim is to combine the numbers in order to get the number displayed. Of course, the further you go, the more difficult it gets!
The ad-free version of "CalQ" drops in price today, from £0.72 to £0.