Answer:
Explanation:
So we know that it cost $600 in material to build the couch,
and then we know it cost $2000 extra to install and setup the couch,
so it cost 2,600 to build and install one couch,
So the first answer is 2,600
Now to build and install 15 of them we do 2,600 x 15 = $39,000
So it cost 2,600 to make and install one
And 39,000 to make and install 15.
But it only cost $600 to build one
and $9,000 to make 15 without installation fees.