Data:
ice cream cones: x
sundaes: y
Total receipts :T

As the total of cones and sundaes is 178:

The total receipts were: $294.20

1. Solve one of the variables in one of the equations:
Solve x in the first equation:

2. Use this value of x in the other equation:

3. Solve y:

4. Use the value of y=84 to find the value of x:

Then, the ice cream parlor sold 88 cones and 84 sundaes