Perfect matching

Ok kiddo, imagine you have a big box of socks. Some of the socks are red and some are blue. You want to find a way to match all the socks up so that each red sock has a blue sock to go with it. That means every sock has a partner and there are no leftover socks.

In math, we call this a "perfect matching" and it's when every item in one group (the red socks) is matched up perfectly with one item in another group (the blue socks). It's like a puzzle where you have to find the right partners for each piece.

Now, imagine you have more red socks than blue socks. What do you do with the extra red socks? They can't have a partner, right? So you can't have a perfect matching.

In math, we call this an "imperfect matching" because not all the items in one group can be matched up perfectly with items in another group. So if you want a perfect matching, you need to have the same number of items in each group.

I hope that helps you understand what a perfect matching is!