The rush-hour traffic flow (in vehicles per hour) for a network of four one-way streets is shown in the figure. 

(A) Write the system of equations determined by the flow of traffic through the four intersections. 

(B) Find the solution of the system in part (A). 

(C) What is the maximum number of vehicles per hour that can travel from Oak Street to Elm Street on 1st Street? What is the minimum number? 

(D) If traffic lights are adjusted so that 500 vehicles per hour travel from Oak Street to Elm Street on 1st Street, determine the flow around the rest of the network.

Transcribed Image Text:

700 600 1st St. 300 X4 500 X1 X3 2nd St. 200 X2 600 300 400 Elm St. Oak St.