- Ram starts working on a job and works on it for 12 days and completes
40% of the work. To help him complete the work, he employs Ravi and together
they work for another 12 days and the work gets completed. How much more
efficient is Ram than Ravi?
(1) 50% (2) 200% (3) 60% (4) 100%
Solution:
Ram completes 40% of work in 12 days.
i.e. another 60% of the work has to be completed by Ram and Ravi. They have taken 12 days to complete 60% of the work.
Therefore, Ram and Ravi, working together, would have completed the entire work in (12/60)*100 = 20 days.
As Ram completes 40% of the work in 12 days, he will take (12/40)*100 = 30 days to complete the entire work
Working alone, we know Ram takes 30 days to complete the entire work. Let us assume that Ravi takes 'x' days to complete the entire work, if he works alone. And together, they complete the entire work in 20 days.
Therefore, (1/30) + (1/x) = (1/20) => (1/x) = (1/20) - (1/30) = (1/60)
Therefore, Ravi will take 60 days to complete the work, if he works alone.
Hence Ram is 100% more efficient than Ram.
