A shopkeeper expects a gain of 22 1/2% on his cost price. If in a week, his sale was of Rs. 392, what was his profit ?

\par C.P. = Rs. \left(\frac{100}{122.50}\times 392)\right)

          

\par = Rs. \left(\frac{1000}{1225}\times 392)\right)

          

\par = Rs. 320

\par Profit = Rs. (392 - 320) = Rs.72