Use the image to answer the question.

An illustration shows Quadrant 1 of a coordinate plane. The x-axis is labeled Ounces and ranges from 0 to 40 in 5 unit increments. The y-axis is labeled Cost in dollars and ranges from 0.00 to 4.00 in increments of 0.50. The graph is titled Cost per Ounce. A line connects four points plotted on the graph. The coordinates of the plotted points are left parenthesis 0 comma 0 right parenthesis, left parenthesis 8 comma 0.80 right parenthesis, left parenthesis 15 comma 1.50 right parenthesis, and left parenthesis 30 comma 3.00 right parenthesis.

Store A and Store B are advertising canned corn on sale. Store A’s canned corn cost per ounce is displayed in the graph. Store B’s canned corn is represented by the equation y=0.13x
. Which store has the better buy and by how much?

(1 point)
Responses

Store B has the better buy by $0.13 per ounce.
Store B has the better buy by $0.13 per ounce.

Store B has the better buy by $0.03 per ounce.
Store B has the better buy by $0.03 per ounce.

Store A has the better buy by $0.03 per ounce.
Store A has the better buy by $0.03 per ounce.

Store A has the better buy by $0.10 per ounce.

1 answer

To determine which store has the better buy, we need to compare the cost per ounce of canned corn for both Store A (represented by the graph) and Store B (represented by the equation \( y = 0.13x \)).

From the graph:

  • At \( x = 8 \) ounces, Store A's cost is \( 0.80 \) dollars, so the cost per ounce is \( \frac{0.80}{8} = 0.10 \) dollars per ounce.
  • At \( x = 15 \) ounces, Store A's cost is \( 1.50 \) dollars, so the cost per ounce is \( \frac{1.50}{15} = 0.10 \) dollars per ounce.
  • At \( x = 30 \) ounces, Store A's cost is \( 3.00 \) dollars, so the cost per ounce is \( \frac{3.00}{30} = 0.10 \) dollars per ounce.

Store A consistently has a cost of \( 0.10 \) dollars per ounce.

For Store B:

  • The equation for cost per ounce is \( y = 0.13x \).
  • To find the cost per ounce, we use the ratio with the ounces: \[ \text{Cost per ounce for Store B} = \frac{y}{x} = \frac{0.13x}{x} = 0.13 \text{ dollars per ounce}. \]

Now we can compare the costs per ounce:

  • Store A: \( 0.10 \) dollars per ounce
  • Store B: \( 0.13 \) dollars per ounce

Since \( 0.10 < 0.13 \), Store A has the better buy.

To find the difference: \[ 0.13 - 0.10 = 0.03 \text{ dollars per ounce}. \]

Thus, the final answer is:

Store A has the better buy by $0.03 per ounce.