The sale price of a trolley bag including the sale tax is Rs. 420. The rate of sale tax is 12% . If the shopkeeper has made a profit of 25%, the cost price of the trolley bag is:	Choose the correct choice from the following answers.
A) rs 625 B) rs 300 C) rs 350 D) rs 375 E) none of these

Rationale: explanation : 112 % of s . p . = 420 s . p . = rs . ( 420 x 100 / 112 ) = rs . 375 . c . p . = rs ( 100 / 125 x 375 ) = rs 300 answer : b
Answer: B