In a zoo, the ratio of the number of cheetahs to the number 4 then what is the increase in the number of pandas?  Answers
A) 2 B) 12 C) 5 D) 10 E) 15

Rationale: one short cut to solve the problem is c : p = 1 : 3 c increased to 5 = > 1 : 3 = 5 : x = > x = 15 = > p increased by 12 b is the answer
Answer: B