Systems and Center of Mass Practice Test

A system consists of three point masses: $$m_1 = 2.0\text{ kg}$$ at position $$x_1 = 0\text{ m}$$, $$m_2 = 3.0\text{ kg}$$ at position $$x_2 = 4.0\text{ m}$$, and $$m_3 = 1.0\text{ kg}$$ at position $$x_3 = 6.0\text{ m}$$. What is the $$x$$-coordinate of the center of mass of this system?

Two objects with masses $$m_1 = 4.0\text{ kg}$$ and $$m_2 = 8.0\text{ kg}$$ are connected by a light rigid rod of negligible mass. If the center of mass of the system is located $$2.0\text{ m}$$ from $$m_1$$, what is the distance between the two masses?