Fraction is defined as the representation of a whole into equal parts. In a fraction, the numerator is the possible number of equal parts and the denominator is the number of those parts making a whole.
The correct answer for the blank is:
A fraction is written in simplest form when the GCF of the numerator and the denominator is 1.
The greatest common factor or the highest common factor is the largest number, which is the factor of each number of the fraction, group, or given quantitative series.
The simplest form of the fraction is written in simplest forms when the numerator and denominator have the greatest common factor as 1.
The number 1 is a factor of every number, such that the two prime numbers will also have a GCF one, and the two multiples can also have the GCF 1.
Therefore, the correct answer is 1.
To know more about GCF, refer to the following link:
https://brainly.com/question/11221202
