what is the mean graphs?

 

https://docs.google.com/drawings/d/177h8QE4Xon5k3bq770rkjTDq88NaHGs00Ga3z6lNiGk/edit 

so its like you are trying to find the same number and add then up and find your answer and to like if you have 2 and other 2 and a 4 the you look for the number that are the same so yeah.