how many kg of pure salt must be added to 100 kg of 10 % solution of salt and water to increase it to a 12 % 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 ) = 12 / 100 250 + 25 x = 300 + 3 x 22 x = 50 x = 2.3 answer is b"
divide(subtract(12, 10), subtract(const_1, divide(12, 100)))