1. **State the problem:** We need to find the amount of sugar required to make 25 medium sized pancakes, given that 2 tablespoons of sugar are needed for 10 pancakes. 2. **Identify the formula:** The amount of sugar is proportional to the number of pancakes. We use the ratio: $$\frac{\text{sugar}}{\text{pancakes}} = \frac{2}{10}$$ 3. **Set up the proportion:** Let $x$ be the amount of sugar needed for 25 pancakes. $$\frac{2}{10} = \frac{x}{25}$$ 4. **Solve for $x$:** Cross-multiply: $$2 \times 25 = 10 \times x$$ $$50 = 10x$$ 5. **Divide both sides by 10:** $$\cancel{10}x = \frac{50}{\cancel{10}}$$ $$x = 5$$ 6. **Interpret the result:** Tima needs 5 tablespoons of sugar to make 25 medium sized pancakes.