A. 94 kg
B. 84 kg
C. 109 kg
D. 104 kg
🧠 Explanation:
Three boxes’ average weight increases by 5 kg when a 89 kg box is replaced by a 104 kg box. Solve: new box = 89 + 3 × 5 = 104. This teaches students how to solve average problems in math or real-world scenarios.