physics
posted by sandhu .
An 3730 kg airplane has a center of mass located 32 m from the front of the plane. A 123 kg man sits 25 m from the front of the plane. Where should a 76 kg woman sit so that the center of mass of the loaded plane is the same as the empty airplane? (m from front)

Take moments about the centre of gravity (CG) the plane, so that the CG of the two persons is zero about the C from the front.
F........M...7...CG....X....W.......B
Take moments about the CG:
123 kg *7 m= 76 kg * X m
X = (123/76) * 7
= 11.33m (from the CG)
Distance from the front
=32+11.33 m
= 43.33 m from the front 
Thanks a lot