Step 1: Compare the two averaging methods:
Simple average method gives every year's profit the same weight and suits a firm whose profits stay roughly equal, showing no real trend.
Step 2: Reason about weighted averaging:
Weighted average deliberately gives more weight to the most recent year(s), which is meaningful only when profits are genuinely rising — the latest, higher figures then more fairly represent future earning capacity than older, lower figures.
Final Answer:
Weighted average method is used when profit has an increasing trend.