A couple wants to invest up to $20000. They can purchase a type A bond yielding 8.75% return and a type B bond yielding a 13.75% return on the amount invested. They also want to invest at least as much in the type A bond as in the type B bond. They will also invest at least $10000 in type A and no more than $16000 in type B bond.
How much should they invest in each type of bond to maximize their return?

Let $x$ be the amount invested in type A bond and $y$ the amount invested in type B bond.

a) Write the objective function to be maximized.
  $P =$

b) The feasible region has 3 corner points. List the three points:
Corner points:

c) Determine the amount to be invested in each bond to maximize the return and determine the maximum return:
Amount to be invested in type A bonds:  $
Amount to be invested in type B bonds:   $
Maximum return is:  $