Answer:
The total cost of one hot dog, one slice of pizza and one ice cream cone at the county fair is $3.
Explanation:
Let us assume that the cost of the one hot dogs be x.
Let us assume that the cost of the one ice cream cone be y.
Let us assume that the cost of the one silce of pizza be z.
As given
At the county fair, two hot dogs and an ice cream cone cost $2.50.
Than the equation becomes
2x + y = 2.50
Two slices of pizza and an ice cream cone cost $3.50.
2z + y = 3.50
Than two equations are
2x + y = 2.50 and 2z + y = 3.50
Adding the both above equation.
2x + y + 2z + y = 2.50 + 3.50
2x + 2z + 2y = 6
x + y + z = 3
Therefore the total cost of one hot dog, one slice of pizza and one ice cream cone at the county fair is $3.