Using a system of equations, it is found that:
- Each pound of strawberry cost $3.
- Each pound of grape cost $1.25.
- Each pound of melon costs $4.75.
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For our system, we have that:
- x is the cost of a pound of strawberry.
- y is the cost of a pound of grape.
- z is the cost of a pound of melon.
Three pounds of strawberries, five pounds of grapes, and one pound of melon at a cost of $20.
This means that:


Three pounds of strawberries, two pounds of grapes, and two pounds of melon at a cost of $21.
This means that:




Four pounds of strawberries, three pounds of grapes, and three pounds of melon at a cost of $30.
This means that:




For x and y, the system is:


Multiplying by 5 and -3, we get:


Then, adding them:



Each pound of grape cost $1.25.
Solving for x:





Each pound of strawberry cost $3.
Finally, for z:



Each pound of melon costs $4.75.
A similar problem is given at brainly.com/question/17096268