You get shown two numbers which are either added or subtracted to provide an answer.
You click on Correct or Wrong. If you click correctly you earn 50 points, if you get it wrong you lose 100 points. You get 60 randomly generated questions to have a go at and you also need to answer as fast as you can.
Your score is; points gained x time taken x 3
– It’s a lot trickier than it looks!
Available from the Windows Store HERE