Two stars of masses m1 and m2 separated by distance d orbit their common centre of mass.

Time period: T = 2pisqrt($d^3$ / (G(m1+m2)))

Each star orbits the CM: r1 = m2*$\frac{d}{m1+m2}$, r2 = m1*$\frac{d}{m1+m2}$

Both have the same angular velocity: omega = 2*pi/T

This extends Kepler's third law to binary systems. JEE Advanced sometimes asks this, and JEE Main occasionally tests the basic concept.