Correct Answer - Option 2 : 6 hrs
Given:
Tap can fill a tank in = 10 hours
Concept:
Time = remaning capacity/efficiency
Calculation:
Let, the capacity of of tank = 10 unit
Efficiency of tank = 10/10 = 1 unit
Half tank capacity = 10/2 = 5 unit
It will be filled in 5 hours
According to the questin,
Total tap opened = 1 + 4 = 5
Total capacity of 5 taps = 5 unit/h
5 taps can fill the tank in,
⇒ 5/5 = 1
Total time = 5 + 1 = 6 hours
∴ The total time taken to fill the tank completely is 6 hours.
