1. **State the problem:** Estimate the difference $1 \frac{1}{3} - \frac{5}{6}$ using number lines and benchmarks. 2. **Convert mixed number to improper fraction:** $$1 \frac{1}{3} = \frac{4}{3}$$ 3. **Find a common denominator to subtract:** The denominators are 3 and 6. The least common denominator is 6. 4. **Convert fractions to have denominator 6:** $$\frac{4}{3} = \frac{4 \times 2}{3 \times 2} = \frac{8}{6}$$ 5. **Subtract the fractions:** $$\frac{8}{6} - \frac{5}{6} = \frac{8 - 5}{6} = \frac{3}{6}$$ 6. **Simplify the fraction:** $$\frac{3}{6} = \frac{\cancel{3}^1}{\cancel{6}^2} = \frac{1}{2}$$ 7. **Estimate using benchmarks:** $1 \frac{1}{3}$ is about 1.33, $\frac{5}{6}$ is about 0.83, so the difference is about 0.5. 8. **Interpretation:** The actual difference $\frac{1}{2}$ matches the estimate from the number lines and benchmarks. **Final answer:** $$1 \frac{1}{3} - \frac{5}{6} = \frac{1}{2}$$