Addition and subtraction are fundamental operations used to combine, separate, or compare quantities. For example, a picture of one apple on a table is visibly different from a picture showing multiple apples or none at all. When a single apple is added to a group of apples, the total number of apples increases. This process, known as addition, determines the new quantity by counting all the apples together. Conversely, subtraction is used to determine what remains when quantities are separated or removed.

Example 1. 8 + 1 = 9

Example 2. 12 – 7 = 5

Example 3. 78 + 96 = 70 + 90 + 8 + 6 = 160 + 14 = 174

Example 4. 345 + 28 = 350 + 23 = 373

Example 5. 864 – 593 = 864 – 600 + 7 = 271