Are they only eating beans or it a single veg as part of a dinner meal.How can we give a reasonable answer if you don't give us all the facts.
At least 18 cans
7
10 cans
I would use 150 cans
10
a 10 lb can of green beans will feed 50 people with 3 oz portions.
I would use 25 pounds of fresh green beans for 100 people
I would NEVER feed guests canned beans. -Fresh are tastier, healthier and only a fraction more costly.
100
You need about 10 twenty eight ounce cans
One normal size can would do 2-3 people, depending on how big a portion they want.
presumably they are having other food also. So 10 people should use 3 can of beans
14 cans
10
it depends on how much people want!