Which of the following modifications to the list of assets and liabilities below would result in a positive net worth? home owned $105,000. mortgage owed $100,000. car valued at $26,000. car loan of $22,000. investment fund of $4,500. savings of $1,500. credit card balance of $15,000.

His home is worth 105,000. That increases his net worth (but the mortgage negates most of that).
His car is worth 26000 but the loan is worth 22000 which negates most of the value of the car.
Investment fund and savings increase his net worth, but the credit card eats up another 16000. Yes he can pay the credit card off monthly, but he should never have run it up as much as he has.

In actual fact, he has little of his own that could be called net worth.
The house is net 5000
 The car is net 4000
The two small funds give 6000
So far the assets number 15000
But the credit card is a debt that wipes out everything else. His best course of action is pay off the card as quickly as possible. The interest is going to eat him alive.