To determine how the amount of money Jackson has changed, we need to calculate the difference between the initial amount of money he had and the final amount of money he has after the transactions.
1. Initial Amount: Jackson had $0, assuming he had no money before these transactions.
2. Transaction 1: Jackson buys a meal for his family for $18, which means he spent $18.
- Amount spent: $18
- New balance: $0 - $18 = -$18 (since he spent more money than he had)
3. Transaction 2: Jackson's friend pays him back the $5 he borrowed last week, which means he received $5.
- Amount received: $5
- New balance: -$18 + $5 = -$13
So, the amount of money Jackson has changed from $0 to -$13 over the course of these two transactions.