After giving three successive discounts of 15%, 5% and p%, respectively, on the marked price of an article of Rs. 4,800, It is sold for Rs. 3,100.80. What is the value of p?
A certain number of persons can complete a work in 54 days. If there were 15 persons less, it would take 18 days more for the work to be completed. Initially, the number persons is: