How many kg of pure salt must be added to 100kg of 10% solution of salt and water to increase it to a 30% solution?
Choose the correct choice from the following answers:
A) 6.7	B) 1.3	C) 9.6	D) 12.5	E) 28.6

Rationale: "amount salt in 100 kg solution = 10 * 100 / 100 = 10 kg let x kg of pure salt be added then ( 10 + x ) / ( 100 + x ) = 30 / 100 100 + 10 x = 300 + 3 x 7 x = 200 x = 28.6 answer is e"
Answer: E