Final answer:
After deducting the $7.99 cost of the sandwich from the total bill of $16.57, the total cost for two smoothies comes to $8.58. Dividing this by 2 gives us the cost of one smoothie, which is $4.29.
Step-by-step explanation:
The total amount spent was $16.57. The cost of the sandwich including tax was $7.99. To find the cost of each smoothie, we first subtract the cost of the sandwich from the total amount to find the combined cost of the two smoothies. The calculation is as follows:
$16.57 (total amount) - $7.99 (cost of sandwich) = $8.58 (total cost for two smoothies)
Next, divide the total cost for two smoothies by 2 to find the cost of one smoothie:
$8.58 / 2 = $4.29 per smoothie.
Therefore, each smoothie cost $4.29.