What is 27 over 19 in simplest form?

Answer 1

Since the numerator of the fraction is prime, the proper fraction 19/27 is already expressed in its simplest form.

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Correct answer, wrong reason.

The requirement is that the numerator and denominator are coprime, not that either of them is prime. For example,

19/38 can be simplified to 1/2 even though the numerator is prime.

Conversely,

8/9 cannot be simplified even though neither the numerator nor the denominator are prime.

Answer 2

27/19 is in its simplest form.