The meanaerochord program produces the following output:
MEAN AERODYNAMIC CHORD DEFINED BY ex1.nml # y xle c xte 1 -1000.00000 600.00000 200.00000 800.00000 2 0.00000 0.00000 400.00000 400.00000 3 1000.00000 600.00000 200.00000 800.00000 area of wing= 600000.0000 length of MAC= 311.1111 y of MAC= 0.0000 xle of MAC= 266.6667 xte of MAC= 577.7778 x of c/4 of MAC= 344.4444
The mean aerodynamic chord (MAC) lies in the plane of symmetry and is shown in the figure below.