Choose the type of sum you wish to attempt and the level of difficulty. Easy is a 4 x 4 grid and hard is a 6 x 6 grid.

When you pair up a question and answer the square disappears. To complete the game make all the squares disappear.

You start with 2000 points.
For every guess that is wrong you lose 5 points.
You are timed until you successfully pair up a question and answer. This gives you your Time Bonus.

There is an overall Time Bonus for completing the game:
Less than 100 seconds gives 1000 points;
less than 250 seconds gives 750 points;
less than 500 seconds gives 500 points and
less than 1000 seconds gives 250 points.