A plank with m=0.12 kg and 50cm long has one mass of m1=0.11kg sitting on one end and a m2=0.055kg at the other end. Where should the pivot point be to balance the plank?

Answer 1

I figured the equation out
Xcg=(m1x1+m2x2+m3(L/2))/(m1+m2+m3)

m1 = 0.055kg
x1 = 0cm

m2 = 0.11kg
x2 = 50cm

for the plank you need to add
m3 = 0.12kg
and distance is L=50cm

it calculates to Xcg=29.825cm