Finance charge is a fancy words of saying how much extra is Marge going to have to pay for this computer that she wouldn't had to have paid if she paid it all at once. So, she paid 100 dollars up front leaving her to pay a total of 599 dollars in the next 12 months.
So,
= 696
Next take the remaining total and subtract the two:
= 97 dollars.
Therefore Marge will have to make a finance charge of 97 dollars.
The answer would be $796 because your down payment is $100 plus the fact marge had to pay $58 for 12 months there for equaling $696 dollars for the 12 month then adding your down payment of $100 giving you your answer of $796!