1. **State the problem:** Ryan has 18 feet of wood and uses three-fourths of a foot for each ladder step. After making some steps, he has 15 feet of wood left. We need to find how many ladder steps he made. 2. **Identify the formula:** \[ \text{Wood used} = \text{Number of steps} \times \text{Wood per step} \] 3. **Calculate wood used:** Since he started with 18 feet and has 15 feet left, the wood used is: \[ 18 - 15 = 3 \text{ feet} \] 4. **Set up the equation:** Let $x$ be the number of ladder steps. \[ x \times \frac{3}{4} = 3 \] 5. **Solve for $x$:** \[ x = \frac{3}{\frac{3}{4}} \] 6. **Simplify the division:** \[ x = 3 \times \frac{4}{3} \] 7. **Cancel common factors:** \[ x = \cancel{3} \times \frac{4}{\cancel{3}} = 4 \] 8. **Answer:** Ryan made **4** ladder steps.