A shop owner sells 40mtr of cloth and gains SP of 10 mtrs. Find the gain %?
Pick:  A) 33.33 %  B) 40 %  C) 50 %  D) 66.67 %  E) 70 %

Rationale: "here , selling price of 10 m cloth is obtained as profit . profit of 10 m cloth = ( s . p . of 40 m cloth ) – ( c . p . of 40 m cloth ) selling price of 30 m cloth = selling price of 40 m of cloth let cost of each metre be rs . 100 . therefore , cost price of 30 m cloth = rs . 3000 and s . p . of 30 m cloth = rs . rs . 4000 profit % = 10 / 30 × 100 = 33.33 % profit of 33.33 % was made by the merchant . a"
Answer: A