Answer:100
Explanation:
The following information can be gotten from the question:
Cost for 10 sofas = $2500
Cost for 12 sofas = $2760.
Average Cost = Total Cost/Quantity
2500 / 10 = $250 and
$2760 / 12 = $230
The average cost for 12 sofas will be $230
Marginal cost is the change in total cost divided by the change in quantity. This will be:
= ( 2760 - 2500 )/( 12 - 10 )
= 260/2
= 130
The difference between the average cost per sofa for 12 sofas and the marginal cost of the 12th sofa will be:
=230 - 130
= 100