In this case to find the weight of an object you must use the formula.
W = mg
Answer:
center of mass = −0.50 m
Explanation:
given data
mass m1 = 3.04 kg
distance xm = -8 m
mass m2 = 5.61 kg
distance xM = 3.56 m
solution
we get here center of mass for n mass of system that is express as
center of mass =
......................1
but we have only 2 particle system so we will get
center of mass =
.................2
put here value and we will get
center of mass = 
solve it we will get
center of mass = −0.50 m