Chapter 5.5, Problem 20E

In Exercises 9-22, solve the given standard minimization problem using duality: (You may already have seen some of these in earlier sections, but now you will be solving them using a different method.] [HINT: See Example 1]

Minimize $c=2s+2t+3u$ subject to $s+u\ge 100$

$2s+t\ge 50$

$t+u\ge 50$

$s\ge 0,t\ge 0,u\ge 0$.