Calculating the different number of cases and describing them
The council is ordering pizza for their next meeting. There are 20 council members, 7 of whom are vegetarian. A committee of 3 will order 6 pizza from a pizza shop that has a special for a large pizza with up to 3 toppings. The shop offers 10 toppings.
The committee wants as much variety as possible in the toppings. They decide to order each topping exactly once and to have at least 1 topping on each pizza. Describe the different cases possible when distributing the toppings this way.