At a restaurant, customers can order a hamburger, a cheeseburger, or a chicken sandwich as their main dish. With any of these main dishes they can order a side of french fries, onion rings or a salad . What is the total possible outcomes

There are 9 possible outcomes.

There are 3 types of burgers, so 3 events in which a certain burger is chosen, and 3 sides, so 3 events a certain side is chosen.

The total possible outcomes is equal to the number of events multiplied.
3x3 = 9 outcomes