a friendly teacher points to a chalkboard showing apples being crossed out during a math problem. She demonstrates removing three apples from a group of seven drawn apples. The crossed-out apples clearly show what has been taken away or reduced. Four uncrossed apples remain visible on the board showing the final result. Students in the front row watch attentively as she explains the subtraction process. One student raises her hand showing she understands the concept. the process of reduction by taking away or removing items from a larger group