A racing car going at an average speed of 108 km/hr takes 15 minutes to complete a lap on a racing track. By how much should it increase its speed (inkm/hr) to complete the lap in 12 minutes?
Mr. Murthy invested Rs. 16,000 in a scheme. How much will he get on matuirity, if he invested it at 20% per annum C.I. for 9 months, compounded quarterly?