1. **State the problem:** Emma has 190 masks on her wall, which is 38% of her entire mask collection. We need to find the total number of masks in her collection. 2. **Formula used:** To find the total when given a part and its percentage, use the formula: $$\text{Total} = \frac{\text{Part}}{\text{Percentage}}$$ where Percentage is in decimal form. 3. **Convert percentage to decimal:** $$38\% = \frac{38}{100} = 0.38$$ 4. **Set up the equation:** $$190 = 0.38 \times \text{Total}$$ 5. **Solve for Total:** $$\text{Total} = \frac{190}{0.38}$$ 6. **Show intermediate cancellation:** $$\text{Total} = \frac{\cancel{190}}{\cancel{0.38}}$$ 7. **Calculate:** $$\text{Total} = 500$$ **Answer:** Emma's total mask collection has 500 masks.