Question

At store A, 3 pounds of apples cost $12. At store B, the cost is given by y = 2 x where y is the cost in dollars and x is the number of pounds of apples. The cost of apples at store C is shown in the graph.
Answer the questions to find out which store's apples are the least expensive.

1. What is the unit price of apples at store A? Explain how you found this unit price.

2. What is the unit price of apples at store B? How did you use the equation to fi nd the unit price?

3. What is the unit price of apples at store C? How did you use the graph to fi nd the unit price?

4. Which store has the lowest unit price for apples?

Answer 1

Answer:

The unit price is the cost per unit of an item or the cost/price for each item.

1) 4$ per pound. By simplifying the proportion (constant ratio) between the cost, and the pounds of apples. 3 pounds of apples cost 12$ → 3/3 pounds of apples cost 12/3$ → 4 dollars for every pound.

2) 2$ per pound. By evaluating the rate of change (change in the y over x or dependent variable over independent) in the equation: y = 2x. y is the cost in dollars, and x is the pounds of apples. So there are 2 pounds (weight) of apples for every dollar.

3) 3$ per pound. Given a graph with a y scaled by 3, and an x scaled by 1 with a graph y = x or 1 unit up for every unit right. This must be equivalent to y = 3x. Where y is labeled as the cost in dollars, and x as the weight in pounds. So there are 3 dollars for every pound of apples.

4) Store B. Because 2 is less than 3 which is less than 4.

Hope it helps, stay safe and tell me if me wrong! :D