Solution: Based on the properties of classical concepts and probability .

　　Method 1　Treat " choose from different pairs of shoes " as a random experiment, assume that the shoes are taken out one after another, according to the multiplication principle , there are 

ways to choose. Suppose event 

at least of the shoes match ,

Because it involves "at least" and is a sum event, we can first consider the probability of its opposite event and find the number of sample points in

　　Still considering the method of taking out shoes one by one: the first shoe can be taken from any of the shoes, the second shoe can only be taken from any of the remaining shoes that do not match the first shoe, the third shoe can only be taken from any of the remaining shoes that do not match the first two shoes, and the shoe has only ways to take it, so the total number of sample points in  is

,

Therefore, according to the property 3 of probability, we can get 

.

　　Method 2　Still use the symbols in Solution 1, but regardless of the order, take out animals at a time. According to the combination formula, the total number of test results is type the number of sample points for the opposite event is to select pairs of shoes from pairs. then, there are different ways to select one shoe from each pair, therefore, according to the property of probability 3, 

.

　　Method 3　Directly find . Because involves "at least" , which is a sum event , we can set 

of the shoes taken out can be matched into a pair of ,

The shoes taken out exactly match pairs of ,

then,

, and .

The number of sample points in is 

 or   ,

The number of sample points in is . Note that events and are mutually exclusive . According to the property 2 of probability, we have