Add up the constant bills, like rent, food, gas, entertainment, etc. Then decide how much to pay on credit cards with what is left over.
Michelle's annual take-home pay is $29,000. What is the maximum amount that she can spend per month paying off credit cards and loans and not be in danger of credit overload?
I assume you have some kind of breakdown of how much of her take home pay should be allotted to the various common categories of monthly or annual expenses.
Just multiply $29000 by those percents.