10 men working for 20 days, 5 hours a day can build a fence of length 20 meters. I need to build a fence of length 100 metres in 5 days and the men are willing to work 10 hours a day. How many men do we need
Correct Answer : D
A takes 4 days to do a work. B takes twice as long as A. C takes twice as long as B and D takes twice as long as C. They are made in groups of two. One of the groups takes two third of the time taken by second pair. What is the combination of the first pair?
The length of the bridge which a train, 130 metres long and travelling at 45 km per hour, can cross in 30 seconds, is