Microsoft's Minecraft Set to Launch its Own Currency. by. Microsoft Corp. is adding a new marketplace -- and a brand new currency -- within the video-game Minecraft, opening up the opportunity for businesses to sell their original content and creations to tens of millions of the gameâs players for the first time.
In combinatorics, the rule of sum or addition principle is a basic counting principle. Stated simply, it is the idea that if we have a ways of doing something and b ways of doing another thing and we can not do both at the same time, then there are a + b ways to choose one of the actions.
So just to review, addition is you're doing more or something. Subtraction is you are taking away. If you think about it on the number line, addition is increasing along the number line by that amount. So in this case we increased along the number line by 3. And so we went from 4 to 7. In the subtraction case we decrease back on the number line.