Write a function rule for the total cost.
One frozen yogurt store sells frozen yogurt for $3 per cup and $1.25 per topping. Write a linear equation to show the total cost of a cup of frozen yogurt then calculate the total price for one cup of frozen yogurt with 4 toppings
Function rule: Total Cost = 3x + 1.25y, where x is the number of cups and y is the number of toppings.
Total Price = 3(1) + 1.25(4) = $7.25