A man sells a car to his friend at 13% loss. If the friend sells it for Rs.54000 and gains 20%, the original C.P.of the car was :  Choose the correct choice from the following answers
A) rs . 21724.14 B) rs . 31724.14 C) rs . 51724.14 D) rs . 61724.14 E) none of these

Rationale: "explanation : s . p = rs . 54,000 . gain earned = 20 % c . p = rs . [ 100 / 120 ã — 54000 ] = rs . 45000 this is the price the first person sold to the second at at loss of 13 % . now s . p = rs . 45000 and loss = 13 % c . p . rs . [ 100 / 87 ã — 45000 ] = rs . 51724.14 . correct option : c"
Answer: C