Efficiency with which Adam and Mike work is in the ratio 2:1. How much time will they, working together, take to complete a job which Adam alone could have done in 10 days?	Choose the correct choice from the following:
A) 15 days  B) 20 days  C) 6 days  D) 6 1â„3 days  E) None of these
Ratio of times taken by Adam and Mike = 100 : 200 = 1 : 2.   Suppose Mike takes x days to do the work.   Then, 1 : 2 : : 10 : x â‡’ x = (10Ã—2)/1 â‡’ x = 20   Adamâ€™s 1 dayâ€™s work = 1â„10; Mikeâ€™s 1 days work = 1â„20   (Adam + Mike)â€™s 1 dayâ€™s work = (1â„10 + 1â„20) = 3â„20   âˆ´ Adam and Mike together can complete the job in 20â„3 days or 6 2â„3 days.   Answer None of these
<result>E</result>
Efficiency with which Adam and Mike work is in the ratio 2:1. How much time will they, working together, take to complete a job which Adam alone could have done in 10 days?