Drag and drop the number from the right to the number on the left so they both add up to 10.
In other words: Click and hold the button down while moving the number. Release the button when over the other number.
The resources listed below are aligned to the same standard, (1OA06) re: Common Core Standards For Mathematics as the Addition and subtraction game shown above.
Add and subtract within 20, demonstrating fluency for addition and subtraction within ...