in what ratio must rice of rs . 32 per kg be mixed with rice of rs . 42 per kg so that cost of mixture is rs . 20 per kg ?
"( 20 - 42 ) / ( 32 - 20 ) = 22 / 12 = 11 : 6 answer : c"
divide(divide(subtract(20, 42), subtract(32, 42)), subtract(const_1, divide(subtract(20, 42), subtract(32, 42))))