Final answer:
Alejandro borrowed $15.25 and paid back $7.50. By subtracting the amount paid back from the amount borrowed, it is determined that Alejandro still owes $7.75 to his mother.
Step-by-step explanation:
The student is asking a mathematics question related to subtracting one money amount from another. Initially, Alejandro borrowed $15.25 from his mother to go to the movie theater. Subsequently, a week later, he gave his mother $7.50 back.
To find out how much Alejandro still owes his mother, we subtract the amount he paid back from the original amount borrowed:
- $15.25 (amount borrowed)
- - $7.50 (amount paid back)
- = $7.75 (amount still owed)
Therefore, Alejandro still owes his mother $7.75.