by selling an article at rs . 400 , a profit of 25 % is made . find its cost price ?
"sp = 400 cp = ( sp ) * [ 100 / ( 100 + p ) ] = 400 * [ 100 / ( 100 + 25 ) ] = 400 * [ 100 / 125 ] = rs . 320 answer : b"
divide(multiply(400, const_100), add(const_100, 25))