Correct option is E
Information Given:
Pipe A fills tank in 5 hours
Pipe B fills tank in 6 hours
Pipe C fills tank in 30 hours
Concept/Formula Used:
Work rate of all pipes = sum of individual rates
Total time = 1 / (total work rate)
For pipes: rate per hour = 1 / respective time
Explanation:
Pipe A's rate = 1/5
Pipe B's rate = 1/6
Pipe C's rate = 1/30
Combined rate = 1/5 + 1/6 + 1/30 = (6+5+1)/30 = 12/30 = 2/5 tank per hour
Time taken to fill tank = 1 / (2/5) = 5/2 = 2.5 hours