IKMC 2027 - Grades 7-8 - Self-study SET 8 - Thematic Batch 3 Question 7

Three taps A, B and C have constant filling rates. Together they fill a tank in 1 hour; A and C fill it in 1.5 hours; B and C fill it in 2 hours. How many hours do A and B alone need? In every case the taps are opened simultaneously.