Final answer:
The student spent a total of $12 on four avocados, after starting with $23 and having $11 left. Therefore, each avocado cost $3.
Step-by-step explanation:
To solve the question of how much each avocado cost, we start with the total amount of money the student had initially, which is $23. After purchasing the avocados, $11 remained. The difference between the amount before and after purchasing the avocados is the total cost of the avocados.
$23 (initial amount) − $11 (remaining amount) = $12 (total spent on avocados)
Since the student bought four avocados, we divide the total spent by the number of avocados to find the cost per avocado:
$12 (total spent on avocados) ÷ 4 avocados = $3 per avocado
So, each avocado cost $3.