The Sort Race

If you like brain training games you are at the right place. In this game you must think fast and have quick reflexes. The game consists of 42 levels. In each level there will be a number of cards which you need to sort. In each card you must calculate a simple arithmetic operation between a number and an image (representing a number which you must guess). When you make the calculation, in order to sort the card you have to compare the value of the current card with the value of the previous one, so you always need to remember the value of the previous card. To sort the cards there are 3 directions:
1. Swipe right - If the current card has bigger value than the previous one.
2. Swipe left - If the current card has a smaller value than the previous one.
3. Swipe down - If the cards are equal.
The fun part is that based on the level you will have only 2-4 seconds to make the calculation and swipe the card. Of course that is not all, at a random times you will enter in a "Mirror mode", where 
every swipe direction will become the opposite of the original. The swipe directions in the “Mirror mode are”:
1. Swipe right - If the current card has a smaller value than the previous one.
2. Swipe left - If the current card has a bigger value than the previous one.
3. Swipe up - If the cards are equal.