Rei volunteers to bring origami swans and giraffes to sell at a charity crafts fair. It takes her three minutes to make a swan and six minutes to make a giraffe. She plans to sell the swans for $\$4$ dollars each and the giraffes for $\$6$ each. If she only has $16$ pieces of origami paper and can’t spend more than one hour folding, use a geometric approach to find how many of each animal should Rei make to maximize the charity’s profit?

So far, I have:

s: $\#$ of swans

g: $\#$ of giraffe

p: profit, p= 4s+6g


time it takes to make origami (in minutes): 3s+6g $ \leq$ 60

paper: s+g=16

Number of swans: s $\geq$ 0

Number of giraffes: g $\geq$ 0

After this I am unsure as to where to go. We are instructed that we are to use LINGO, but I am unsure how to use the program nor has the teacher taught us, any help is appreciated and thank you.

  • 1
    $\begingroup$ Test for profit at the vertices of this graph. $\endgroup$ Jun 23, 2020 at 23:04
  • $\begingroup$ Why don´t you give any reply (including accepting an answer)? This behaviour doesn´t motivate people to help you. $\endgroup$ Jul 6, 2020 at 5:44

1 Answer 1


If you are to use a geometric approach, I would make the number of swans the horizontal axis and the number of giraffes the vertical axis. Each constraint is a line that divides the feasible from unfeasible region. The sheets of paper form the line $s+g=16$ and the feasible region is below the line. There is another line for the maximum time folding, plus $s \ge 0, g \ge 0$. That gives you a feasible quadrilateral. Now you know the optimal point is at one of the corners of the region, so compute the profit at each one and you have the best point.


You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .