Question: In a bar there are 10 different beer types, 8 wines and 12 whisky types. Jonas would like to take one drink only. How many choices does he have?

There are n elements with property a and m elements with property b. The a and b properties cannot be taken or occur at the same time. Therefore, there are n+m possibilities to select one object with property a or b.

In a car rental company there are 3 small cars and 7 middle-sized cars. When you need to choose one of the cars, you have in total 3+7 possibilities to choose.