In what ratio should a variety of rice costing Rs. 5.5 per kg be mixed with another variety of rice costing Rs. 8.75 per kg to obtain a mixture costing Rs. 7.50 per kg?	Pick one: A) 5 / 6 B) 5 / 9 C) 5 / 1 D) 5 / 8 E) 7 / 6

Rationale: "let us say the ratio of the quantities of cheaper and dearer varieties = x : y by the rule of allegation , x / y = ( 8.75 - 7.50 ) / ( 7.50 - 5.5 ) = 5 / 8 answer : d"
Answer: D