GMAT Critical Reasoning (CR) | Re: Students at Lincoln High School will boycott graduation ceremonies unl

Here is the comprehensive explanation

Remember, “A unless B” is the equivalent
of ~B—>A. The first sentence in the passage
can be depicted as
~BD—>BG
where B D stands for “the administration
allows the band director to keep his teaching
position” and BG stands for “Students at
Lincoln High School will boycott graduation
ceremonies.” The second sentence contains an
implied if-then statement. It can be stated as
follows:
...

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