Problem: if the selling price of 7 articles is same as the cost price of 10 articles . find the gain or loss percentage ?
Rationale: "let the c . p of each article be re 1 . then , s . p of 7 articles = c . p of 10 articles = rs . 10 now , c . p of 7 articles = rs . 7 , s . p of 7 articles = rs 10 gain = rs ( 10 - 7 ) = rs 3 . gain % = ( 3 / 7 × 100 ) % = 43 % answer : d"
annotated_formula: subtract(7, 10)