mutually exclusive – can't happen at the same time

Mutually exclusive means you have to think in terms of time. This event can't happen at the same time.

To remember the meaning of mutually exclusive means can't happen at the same time, use the following mnemonic:

The two mutants (mutually) are excluded (excluded) from entering the club together by time.

Mutually exclusive is about time. The event can't happen at the same time. 

E.g. you can't have both 1 and 2 children. Throwing a dice and obtaining a 6 and 1 are mutually exclusive. You can't be 170cm and 180cm.

Exam: In an exam, examiners will give you full marks if you describe probability questions in the correct way such as these events are mutually exclusive.