1. ~M 2. (~M & ~N) -> (Q -> P) 3. P -> R 4. ~N :. Q -> R 5. ~M & ~N 1, 4 Conjunction Introduction 6. Q -> P 5, 2 Modus Ponens 7. (Q -> P) & (P -> R) 3, 6 Conjuction Introduction 8. :. Q -> R 7 Hypothetical Syllogism