Vishnu travelled equal distances at speeds of 10 kmph, 30 kmph and 8 kmph and took a total of 15.5 min to complete. Find the total distance he travelled, in km.
Manish, Mukesh and Sachin are Accountants. Mukesh can filea return in 5 hours and Sachin in 4 hours alone. All three together can do it in 2 hours. In what time (in hrs) will Manish do the work?