Question

Cherries cost $5 for 2 pounds and $7.50 for 3 pounds.

What is the cost per pound?
b. Is it constant?
c. If you were to graph this situation, would you put weight or cost on the x-axis? Which one would you put on the y-axis?
d. Plot the two points described.
e. How much would 5 pounds of cherries cost? What did you do to solve this problem?

Answer 1

Cherries cost $2.50 per pound

Yes, it is constant.

Weight would go on the x-axis and the cost would go on the y-axis.

The two points are (2, 5) and (3, 7.5)

5 pounds of cherries would cost $12.50. To solve the problem I multiplied the 5 pounds by 2.5, the cost per pound to find the cost.

Explanation:

$5 for 2 pounds and $7.50 for 3 pounds can be turned into the points (2, 5) and (3, 7.5).

To find the cost per pound, input the two points into the slope formula:
`(y2-y1)/(x2-x1)`

`(7.5-5)/(3-2)`

Solve:

7.5 - 5 = 2.5

3 - 2 = 1

`(2.5)/(1)` = 2.5

The cost of cherries per pound is $2.50. This is our slope.

The equation that represents the cost of cherries for x amount of pounds is:

y = 2.5x

To find how much 5 pounds of cherries would cost, replace x with 5 in the equation:

y = 2.5(5)

y = 12.5

5 pounds of cherries would cost $12.50.

I hope this helps :)