in what ratio should a variety of rice costing rs . 20 per kg be mixed with another variety of rice costing rs . 31.50 per kg to obtain a mixture costing rs . 23.75 per kg ?
"let us say the ratio of the quantities of cheaper and dearer varieties = x : y by the rule of allegation , x / y = ( 31.50 - 23.75 ) / ( 23.75 - 20 ) = 31 / 15 answer : d"
divide(divide(subtract(31.50, 23.75), subtract(31.50, 20)), subtract(const_1, divide(subtract(31.50, 23.75), subtract(31.50, 20))))