1. **Problem:** Compare the lengths of segments MR and RP in triangle MRP where angle R is 21° and angle P is 19°. 2. **Rule:** In any triangle, the side opposite the larger angle is longer. 3. **Step:** Calculate angle M using the triangle angle sum rule: $$\text{Angle } M = 180^\circ - 21^\circ - 19^\circ = 140^\circ$$ 4. **Step:** Identify sides opposite each angle: - Side MR is opposite angle P (19°) - Side RP is opposite angle M (140°) 5. **Step:** Since 140° > 19°, side RP is longer than side MR. 6. **Conclusion:** Therefore, $$\boxed{RP > MR}$$