In a zoo, the ratio of the number of cheetahs to the number of pandas is 1 : 3 and was the same five years ago. If the increase in the number of cheetahs in the zoo since then is 1, then what is the increase in the number of pandas?  Choose the correct choice from the following answers:
A) 2
B) 4
C) 5
D) 10
E) 3
One short cut to solve the problem is   c:p = 1:3   c increased to 2   =&gt; 1:3 = 2:x   =&gt; x = 6   =&gt;p increased by 3   3 is the answer
<result>E</result>
In a zoo, the ratio of the number of cheetahs to the number of pandas is 1 : 3 and was the same five years ago. If the increase in the number of cheetahs in the zoo since then is 1, then what is the increase in the number of pandas?