Part 3/6:
The second aspect of subtraction involves the idea of completing a quantity. For instance:
Example Problem:
Melissa wants to buy a game that costs R$37, but she only has R$23. How much more does she need?
In this example, we subtract the amount Melissa has (R$23) from the total cost of the game (R$37):
- Calculation: 37 - 23
This subtraction yields an answer of R$14, indicating how much more she needs to complete her purchase.
Subtraction as Comparison
The final context for applying subtraction is when comparing two quantities. Consider this scenario:
Example Problem:
Ana and João are collecting aluminum can tabs for a neighborhood charity. Ana collected 206 tabs, while João collected 148. How many more tabs does Ana have than João?