128dot7 - Improve your mental arithmetic skills and agility!

How many minutes do you have left when 139 of 1024 have already passed?
How much money do you need, if you want to buy 17 boxes for $13 each?
If you are older than 16 and need more than 5 seconds or even a pocket calculator for each of those tasks, you should train your mental arithmetic skills.
But it's not just about math. You also need dexterity to master the game.
128dot7 helps you, to playfully train your mental arithmetic skills. Play against the time and improve your skills step by step.
There are ten different levels of difficulty, to test and improve your current set of skills.