A photographer allows a discount of 10% on the advertised price of a camera. The price (in Rs) that must be marked on the camera, which cost him Rs 600, to make a profit of 20% would be
Keerthana takes 9 hrs 20 min in walking a distance and riding back to same place where she started. She could walk both ways in 11 hrs 15 min. The time taken by her to ride back both ways is