how many kg of pure salt must be added to 100 kg of 10 % solution of salt and water to increase it to a 35 % solution ?
"amount salt in 100 kg solution = 10 * 100 / 100 = 10 kg let x kg of pure salt be added then ( 10 + x ) / ( 100 + x ) = 35 / 100 200 + 20 x = 700 + 7 x 13 x = 500 x = 28.5 answer is b"
divide(subtract(35, 10), subtract(const_1, divide(35, 100)))