Question

Suppose your colleague, Marco, says that he will be in Chicago or St. Louis on Friday. On Friday morning, your boss says, "Where is Marco? He’s supposed to be in Chicago, but he’s not there." You reply, "If he’s not in Chicago, then he’s in St. Louis." Is your argument valid?

Answer 1

yes you're argument is valid

Step-by-step explanation:

Marco would have been able to be in St. Louis or Chicago so if he isn't in Chicago he has to be in St. Louis.