Final answer:
The average fixed cost (AFC) is calculated by dividing the total fixed cost of $100 by the output of 20 units, which results in an AFC of $5 per unit.
Step-by-step explanation:
To calculate the average fixed cost (AFC), we need to divide the total fixed cost (TFC) by the quantity of output produced. Given that the TFC is $100 and the output is 20 units, the AFC calculation would be:
AFC = TFC / Quantity
ACF = $100 / 20
AFC = $5 per unit
The AFC therefore is $5 per unit, indicating that for each unit produced, the fixed cost averaged over all units is $5.