What is the smallest number of chickens that can walk in this formation: two chickens in front of a chicken, two chickens behind a chicken, and a chicken between two chickens?

The smallest number of chickens that can walk in the given formation is 3.

Explanation:

Let us assume that the chickens are walking in a line,

Chicken 1--Chicken 2--Chicken 3

Given,

Situation 1: 2 chickens in front of 1 chicken

That is 2 in front of 1 = 2+1=3 chicken

Situation 2: 2 chickens behind 1 chicken

That is 2 behind 1 = 2+1=3 chicken

Situation 3: 1 chicken between 2 chicken

1+1+1=3 chicken

From the 3 situations, we can conclude that the minimum number of chickens can possibly be 3.