Answer: balance is -44 dollars
This indicates he owes 44 dollars
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Explanation:
21 + (-30) = -9 is the balance if we don't account for the overdraft fee
If we do account for the overdraft fee, then -9 + (-35) = -44 is the bank balance.
Note how I'm using negative values to indicate balances in which Nick owes money, rather than it's the amount of money he has. So he owes the bank $44.
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A slightly different way to get the answer is to say
21-30 = -9
-9-35 = -44
This is because adding a negative is the same as subtraction.
