P(L)= 1/5，P(R)= 4/5；

E(X|L)=9，E(X | R)= E(X)+23；

E(X)= P(L)* E(X | L)+P(R)* E(X | R)= 1/5 * 9+4/5 *(E(X)+23)

E(X)= 10 1 min.

The process is a little short, can you understand it?

Note: the number of holes can be divided into five, only one hole leads to the outside of the hole, and the other four holes are all back to their original positions. Every kitten has equal choices, which is more in line with the reality of life.