In what ratio should a variety of wheat costing Rs. 3 per kg be mixed with another variety of wheat costing Rs. 6.25 per kg to obtain a mixture costing Rs. 4.50 per kg?  Answers
A) 8 : 6	B) 7 : 6	C) 5 : 6	D) 7 : 5	E) 6 : 7

Rationale: let us say the ratio of the quantities of cheaper and dearer varieties = x : y by the rule of allegation , x / y = ( 6.25 - 4.50 ) / ( 4.50 - 3 ) = 7 / 6 answer : b
Answer: B