In what ratio must tea at Rs.60 per Kg be mixed with tea at Rs.70 per Kg so that the mixture must be worth Rs.63 per Kg? Choose the correct choice from the following choices
A) 3 : 1  B) 3 : 2  C) 4 : 3  D) 7 : 3  E) none

Rationale: "required ratio = 700 : 300 = 7 : 3 answer d"
Answer: D