We know that Nadie owes:
• $8 for a movie ticket.
,
• $3 for popcorn.
,
• $2 for a soda.
To know the total amount of money Nadie owes, we just need to sum. Remember that negative numbers represent debts.
When numbers have the same sign, we sum and keep the same sign as a result.
Therefore, the right answer is the last choice: -13.