Final answer:
To determine if the price of coffee is proportional to the amount, the price per ounce must remain constant across all bag sizes. If the price per ounce varies, then the price is not proportional. The correct answer depends on Kayla's observations of the price consistency.
Step-by-step explanation:
To determine whether the price of the coffee is proportional to the amount, we need to examine if the cost per unit (such as per ounce) is consistent across different sizes. Proportional relationships in mathematics imply a constant rate or ratio. If Kayla observes that the price per ounce is the same for all three sizes, then the price is proportional to the amount, and the correct answer would be 'Yes, because the price per ounce is constant'.
However, if Kayla finds that the price per ounce changes with different-sized bags, then the price is not proportional to the amount, leading us to the answer 'No, because the price per ounce varies'. Choice 'Yes, because the price increases with the amount of coffee' could potentially be misleading, as increasing prices do not necessarily indicate proportionality unless the price per ounce remains unchanged. The last option, 'Not enough information to determine', may apply if Kayla has not provided the specific prices or amounts for comparison.
In real-life scenarios, such as the coffee market, prices can fluctuate due to supply and demand, as well as other external factors affecting supply chains and production costs. For example, when Vietnam entered the coffee market, an increased supply led to a decrease in price, illustrating how prices can change in relation to factors other than the actual quantity of the product being sold.