this will depend on the size of the jelly beans and if you are referring to an 8 oz cup or a 250 mL cup. You are just going to have to buy some jelly beans and do the experiment for your self. Don't forget you should do three trials when doing an experiment. So it looks like you are going to have to eat a lot of jellybeans. Enjoy!
It depends on how big your serving is :) Assuming the beans are already cooked when you measured your quart, and a normal serving size is 1/2 cup, you'll have 8 servings to share. If your quart of beans are dry and then you cook them, you'll probably end up with 10 cups of cooked beans, or 20 half cup servings.