I'm stuck on a word problem

Question

Juan is making bird houses to sell at a craft show.the cost of making the bird houses is $80 plus $6.25 per birdhouse .he will sell them for $16 each .what is the minimum number of bird houses he must see to make a profit?

Answer 1

Let x = the number of birdhouses.  The cost to build x birdhouses is:

 

      Cost = $80 + $6.25x

 

The revenue, or money that Juan makes from selling x birdhouses is:

 

      Revenue = $16x

 

To make a profit, revenue must exceed cost:

 

      Revenue > Cost

 

      $16x > $80 + $6.25x

 

      $9.75x > $80

 

      x > 8.2

 

Since Juan can't sell 0.2 of a birdhouse, Juan must sell at least 9 birdhouses to make a profit (8 would be too few).