I can tell that it isn't because the GCF of 4 and 6 is 2. The GCF has to be 1 for a fraction to be in its simplest form. 4/6 reduces to 2/3
The GCF of 4 and 5 is 1.
It already simplest form
Check if there are no common factors between the numerator and the denominator.
You can tell that 4/5 is in its simplest form because 5 is a prime number. The 5 is not evenly distributed unless it is by itself or the number 1.
No other number except 1 divides evenly into both 4 and 5, so 4/5 is in simplest form
4 and 13/20
Simplest form in fractions is where the numerator and the denominator do not share any factors other than 1, i.e. they are relatively prime. For instance, 9/12 is not in simplest form, but 3/4 is.
4/5, do you see a common whole number that will evenly divide (with zero remainder) 4 and 5. The answer is "NO", so 4 over 5 is in its simplest form.
1/4 is in its simplest form.
The GCF of 4 and 5 is 1.
4/5 is in its simplest form.
4/5 is the simplest form.