In what ratio should a variety of rice costing Rs. 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?
Choose the correct choice from the following choices:
A) 1 / 2	B) 5 / 9	C) 5 / 1	D) 5 / 3	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 ) = 1 / 2 answer : a
Answer: A