Valid Or Invalid Venn Diagrams

Five identical sweatshirts are placed in a bag. A letter is stiched to the back of each shirt; two of the letters are L’s and three are W’s. Chris, Hugo and Mary each pull out a sweatshirt without looking at it and put it on. Chris can see Mary’s and Hugo’s and correctly deduces, “I cannot tell which letter I have on.” Mary’s only see’s Hugo’s shirt and draws the same valid conclusion. Hugo sees no-ones shirt but uses his logic and is able to tell which letter is on his back. How does Hugo do it? Write a valid arguement that involves Chris’s deduction. Then using that conclusion write a second arguement to justify Hugo’s claim. Using Venn diagrams show your argument.