Two taps P and Q can fill a tank in 24 hours and 18 hours respectively. If the two taps are opened at 11 a.m., then at what time (in p.m.) should the tap P be closed to completely fill the tank at exactly 2 a.m.?
A Rs 100 shirt is offered at 10% discount and a Rs 300 pair of trousers at 20% discount. If Pritam bought 1 shirt and 3 pairs of trousers, what is the effective discount (in %) he got?