I \\I C LVVUI [\\D mnuqunn . ' 9 University INVERNATIONAL COLLEI Exercises: 1. The following network represents traffic flow at an intersection. Determine the solution and state any conditions for positive traffic flow. 300 x1 200 500 600 x 3 100 400 2. The following network represents water flow through pipes. Determine the solution and state conditions for positive flow. What is the maximum flow through x1? Is it possible to close any of the pipes? Why or why not? Example Question: Find the solutions to the following network flow system 20 X3 X1 80 X2 100 Solution: As before set up the equations: 1 O node 1: X1 - X3 = -20 - -20 1 1 0 80 node 2: X1 + X2 = 80 0 1 100 node 3: X2 + X3 = 100 This system solves for X1 20 1 na X2 100 + 1 -1 X3 0 1 OH A must be greater than 20 and less than 100 for positive solutions