Question

Four objects are situated along the y axis as follows: a 2.00 kg object is at +3.00 m, a 3.00- kg object is at +2.50 m, a 2.50-kg object is at the origin, and a 4.00-kg object is at -0.500 m. Where is the center of mass of these objects from the origin?

Answer 1

The center of mass is

$$x_c=\frac{x_1m_1+x_2m_2+x_3m_3+x_4m_4}{m_1+m_2+m_3+m_4}=+1\text{ m}.$$