Question

A water tank has three taps a, b and


c. tap a, when opened, can fill the water tank alone in 4 hours. tap b, when opened, can fill the water tank alone in 6 hours and tap c, when opened, can empty the water tank alone in 3 hours. if taps a, b and c are opened simultaneously how long will it take to fill the tank

Answer 1

1hr 30 min will be the answer