When a plot is sold for Rs. 18,700, the owner loses 15%. At what price must that plot be sold in order to gain 15%?

A.    Rs. 21,000   
B.    Rs. 22,500
C.    Rs. 25,300   
D.    Rs. 25,800
Answer: C

Explanation:

85 : 18700 = 115 : x
 => x =    (18700 x 115/85) = 25300.
Hence, S.P. = Rs. 25,300.