In what ratio mental A at Rs.68 per kg be mixed with another metal at Rs.96 per kg so that cost of alloy (mixture) is Rs.72 per kg?  Pick one
A) 6 : 1	B) 4 : 7	C) 3 : 7	D) 9 : 5	E) 9 : 8

Rationale: "( 96 - 72 ) / ( 72 - 68 ) = 24 / 4 = 6 / 1 answer : a"
Answer: A