Answer: -$25.80
This balance is negative.
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Explanation:
Start with -42.30 and add on 16.50
-42.30+16.50 = -25.80 is the final balance
The negative balance means Marcos owes this amount of money to the bank. This is true even though he deposited $16.50; he would need to deposit another $25.80 to get out of debt (this is assuming that there aren't any other bank fees coming down the line).
We can think of -42.30+16.50 as 42.30-16.50, but then make the result negative since -42.30 has a larger absolute value compared to 16.50
