All prime numbers are either even or odd, Is it a true statement

logicpropositional-calculus

$r:$All prime numbers are either even or odd, Is it a true statement?

I was studying Mathematical Logic then i came across above question.
Since here connecting word is "OR"
so if i separate two statement then it become

$p:$ All the prime number are even

$q:$ All the prime number are odd

Because both statement $p$ and $q$ are false so final statement $r$ must be false using truth value of statement for "OR" connective.

But my intuition says $r$ is true.

Am i thinking correct?

Please Help me in this.

Best Answer

You erroneously distributed the “all”. The correct interpretation is:

For every prime $p$: $p$ is even or $p$ is odd

Since every integer is either even or odd, we have:

($p$ is even or $p$ is odd) is true for all primes $p$

Therefore it is true — as your intuition suggested

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