Let’s take the square of side \( a \), with O at the center. Coordinates:
- A(0, a), mass = \(2m\)
- B(a, a), mass = \(4m\)
- C(a, 0), mass = \(2m\)
- D(0, 0), mass = \(2m\)
Using the center of mass formula:
\[
x_{cm} = \frac{\sum m_i x_i}{\sum m_i} = \frac{2(0) + 4(a) + 2(a) + 2(0)}{2 + 4 + 2 + 2} = \frac{6a}{10} = 0.6a
\]
\[
y_{cm} = \frac{2(a) + 4(a) + 2(0) + 2(0)}{10} = \frac{6a}{10} = 0.6a
\]
So, the center of mass lies along OB, as it lies closer to the heavier mass (4m at B).