VTMO 2026 - Grade 9 - Semifinal - SET 04 - Self-study Question 13

An starts 100 m west of Bình and Châu 160 m east of Bình. An walks south at 20 m/min and Châu north at 41 m/min, starting together, while Bình stays still. When is Châu's distance from Bình twice An's distance from Bình?