A shopkeeper charges ₹1.50 to photocopy a sheet of paper and a discount of 5.5% is given on all photo copies done after 400 sheets. How much will it cost to photocopy 800 sheets of paper?
P and Q can complete a work in 9 days and 15 days, respectively. If they work together for three days, then in how many days will the remaining work be completed by Q alone?