1. **State the problem:** There are 25 buttons in total, with 12 black buttons and the rest white. We need to find how many buttons are white. 2. **Formula and explanation:** The total number of buttons is the sum of black and white buttons. $$\text{Total} = \text{Black} + \text{White}$$ 3. **Calculate the number of white buttons:** $$\text{White} = \text{Total} - \text{Black}$$ Substitute the values: $$\text{White} = 25 - 12$$ 4. **Simplify:** $$\text{White} = 13$$ 5. **Answer:** There are 13 white buttons.