25 persons can complete a work in 60 days. They started the work. 10 persons left the work after x days. If the whole work was completed in 80 days, then what is the value of x ?
Two bullets were fired at a place at an interval of 28 min 30 sec. A person approaching the firing point in his car hears the two sounds at an interval of 27 mins. The speed of sound is 330 m/s. What is the speed of car?
Anu can complete a piece of work in 22 days. Shama is 60% more efficient than Anu. How many days does Shama alone take to complete the same piece of work?