1. **State the problem:** Isabel has 25 raspberries and eats two fifths of them. We need to find how many raspberries she has eaten. 2. **Formula used:** To find a fraction of a quantity, multiply the fraction by the total quantity. 3. **Apply the formula:** The fraction eaten is $\frac{2}{5}$ and the total raspberries are 25. 4. **Calculate:** $$\text{Raspberries eaten} = \frac{2}{5} \times 25$$ 5. **Simplify:** $$= \frac{2 \times 25}{5} = \frac{50}{5} = 10$$ 6. **Interpretation:** Isabel has eaten 10 raspberries. **Final answer:** Isabel has eaten **10** raspberries.