Answer:
The new credit card balance is $88
Explanation:
The balance of a credit card is what we owe to the credit card company.
Therefore to get the new balance we start with the given previous balance of $186 and then we add to it the value of items you purchased (Books: $174, CDs: $35, shoes $99) and then you subtract the payment of $406 that you did to the company:

Therefore, you now owe to the credit card company $88 that is the new balance.