Question : A graph has 11 vertices classified as follows: six vertices have degree 3, one vertex has degree 4, two have degree 5 and two have degree 6. How many edges does this graph have?
I started to draw the graph but I could not fit with the requirements. I draw first the vertex with largest degrees (6, after 5 etc) but at the end it does not work.
What is the easiest way to approach this problem?