Consider the number of deluxe hambergers is $\"\"$ , the number of large fries is $\"\"$ and the number of large coals is $\"\"$ .

The equation for first group customers is $\"\"$ .

The equation for second group of customers is $\"\"$ .

The system of equations are $\"\"$

The system of equations involving only two equations that contain three or more unknowns cannot be solved uniquely.

There is no sufficient information to determine the price of each food item.

Multiply the equation $\"\"$ by $\"\"$ and add to the equation $\"\"$ to eliminate $\"\"$ .

$\"\"$

Substitute $\"\"$ in equation $\"\"$ .

$\"\"$

$\"\"$ .

The solutions of the system are $\"\"$ and $\"\"$ .

Since $\"\"$ the values of $\"\"$ are $\"\"$ and $\"\"$ .

The possible values of $\"\"$ are shown in table.

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The system of equations involving only two equations that contain three unknown values.

There is no sufficient information to determine the price of each food item.

The solutions of the system are $\"\"$ and $\"\"$ and $\"\"$ .

The possible values of $\"\"$ are shown in table.

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