Application of hyperbola in real-life situations

Question

Two radio signaling stations A and B are 120 kilometers apart. The radio signal from the two stations has a speed of 300 000 kilometers per second. A ship at sea receives the signals such that the signal from station B arrives 0.0002 seconds before the signal from station A. What is the equation of the hyperbola where the ship is located? Set the midpoint of A and B as the origin.

Answer 1

r_A - r_{B = 300000 = 2a = 60 km; a = 30 km; c = 120/2 = 60 km}

b² = 60² - 30² = 270

x²/900 - y²/2700 = 1