Formula Checkbox to Handle an Either Or Criteria

I am trying to setup a workflow trigger to tell the users when a report package is ready for the next phase. We've added an optional task in that process for when there are revisions that need to be done between the reviews. So, I need to know when one or both tasks (if it exists) are completed before signaling that the next stage should begin.

This is an example of the single task formula I am currently using in a Checkbox Field.

If([# of Completed 1st Reviews]>0, true, false)

How would I get the same thing to happen if it needed to also check for the 1st Revisions task? There is a field on the record that says the 1st Revisions task is needed.

Parent Record is Reports, Child Record Tasks, and "# of ____" fields are summary fields on the Parent records. ​

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Jennifer Peterson
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