Final answer:
To determine which store earned more without calculation, compare the quantity sold; higher quantity equals more revenue at a constant price.
Step-by-step explanation:
To determine which store earned more money from the sales of medium bags of trail mix without doing the actual calculations, one would need to compare the quantity of medium bags sold by each store. Since both Patsy's and Mo's sell the medium bags for the same price of $8.49, the store that sold the greater number of bags would have made more money. This is similar to the example provided where the sale of a single pack of raspberries for $8 implies that more packs sold will lead to higher revenue. Therefore, the key is the number of bags sold rather than the price, which remains constant between the two stores.