For a generous portion, 20 pounds of dried beans.
3000 since the average serving contains 150 beans.
I would do 22 pounds of beans
A half a cup of baked beans is a serving. To serve 100 people, you would need about 50 cups of baked beans. You might want to make a little more to account for people taking more than one serving.
Depends on the cup. If it's a McDonalds Large-cup, you probably need 800 grams of baked beans.
Are they ONLY eating beans, -If other items are on the menu then YOU need to tell us to get a proper answer. If they are only having beans I would make about 100 pounds of beans.
Baked beans in a can are already cooked all you need to do is heat them, 20 to 30 minutes in a slow cooker should be enough.
You need about 10 twenty eight ounce cans
As part of a meal one 17 ozs can will feed 2 people so you need 100 cans.
how much pinto beans do I need to cook for 30 people for one meal
No. You just need your measuring cup.
After you open a can of baked beans, you should refrigerate the leftovers in a separate container. (the opened can would rust in the fridge)
presumably they are having other food also. So 10 people should use 3 can of beans