Simple Add Subtract

This is a brain exercise game that does only simple adding and subtracting with maximum 2 digits.
A result and 36 numbers are given. Find the numbers that add up equal to the given result. there are 18 sets or combinations for "add 2 numbers", 12 for "add 3 numbers", 9 for "add 4 numbers" and 6 for "add 6 numbers".
In a relax mood, use adding and subtracting to find the right set or combination. This will keep human brain in light function with calculation and get aways from any other things.
The "Live Result" and the "Display Hint" button are off at default. They can be turned on at the setting scene if it is needed.
The letter and background colour of the 36 number boxes can be changed at the setting scene.