Problem 9BSC

Determining Whether Events Are Disjoint. For Exercise, determine whether the two events are disjoint for a single trial. (Hint: Consider “disjoint” to be equivalent to “separate” or “not overlapping.”)

Randomly selecting a drug screening result and getting one that is a false negative.

Randomly selecting a drug screening result and getting one from someone who is not a drug user.

Solution 9BSC

A person who is not a drug user cannot get the result false negative. So events ‘Randomly selecting a drug is screening result and getting one that is a false negative’ and ‘Randomly selecting a drug screening result and getting one from someone who is not a drug user.’ cannot occur simultaneously. Hence events are disjoint.