Find the ratio in which rice at Rs. 7.10 a kg be mixed with rice at Rs. 5.70 a kg to produce a mixture worth Rs. 6.30 a kg Choices:
A) 2 : 0
B) 3 : 4
C) 2 : 1
D) 2 : 2
E) 2 : 8

Rationale: "by the rule of alligation : cost of 1 kg rice of 1 st kind cost of 1 kg rice of 2 nd kind required ratio = 60 : 80 = 3 : 4 answer : b"
Answer: B