In the example used to demonstrate model construction in this chapter (p. 4), a firm sells a prod- uct, x , for $20 that costs $5 to make, it has 100 pounds of steel to make the product, and it takes...

1. 
   

   In the example used to demonstrate model construction in this chapter (p. 4), a firm sells a prod- uct,
   x, for $20 that costs $5 to make, it has 100 pounds of steel to make the product, and it takes 4 pounds of steel to make each unit. The model that was constructed is

   
   

maximize
Z= 20
x- 5
xsubject to

4
x= 100

Now suppose that there is a second product,
y, that has a profit of $10 and requires 2 pounds of steel to make, such that the model becomes

maximize
Z= 15
x+ 10
ysubject to

4x+ 2y= 100