$\frac{10}{20}=\frac{x}{24}$

Step 1 ：1. Cross-multiply: \(10 \times 24 = 20 \times x\)

Step 2 ：2. Simplify the equation: \(240 = 20x\)

Step 3 ：3. Solve for x: \(x = \frac{240}{20}\)

Step 4 ：4. Final Answer: \(\boxed{x = 12}\)