This was the best diagram/explanation I could come up with.
I really hope this will help you! :)
Hope this helped!
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Paula would choose the side with all of the mushrooms and half of the pepperoni. She wont choose any sausage because she doesn't like it, but luckily David likes sausage twice as much as mushroom so he's fine with getting all of the sausage and half of the pepperoni. They both equally like pepperoni so it makes sense for them to share.