Answer to Question #259742 in Discrete Mathematics for rtf

Question

Refer to the menu below, how many dinners at Kay’s Quick Lunch consist of an optional appetizer, one main course, and an optional beverage? 

Appetizers

Nachos 2.15

Salad 1.90

Main courses

Hamburger 3.25

Cheeseburger 3.65

Fish filet 3.15

Beverages

Tea .70

Milk .85

Cola .75

Root Beer .75

Answer 1

Taking into account that an optional appetizer can be chosen by 2 ways, one main course can be chosen by 3 ways, and an optional beverage can be chosen by 4 ways, we conclude by Combinatorial Product Rule that the number of dinners at Kay’s Quick Lunch consisting of an optional appetizer, one main course, and an optional beverage is equal to $2\cdot 3\cdot 4=24.$