Because odd numbers don't have any even factors so they can't have any in common.
If X and Y are two odd numbers then 2 cannot be a factor of either X nor of Y. That implies that 2 cannot be a common factor and so 2 cannot be a factor of the GCF.
The GCF of any two odd numbers is always odd. The GCF of any two even numbers is always even. The GCF of an odd and an even number is always odd.
The GCF of any two odd numbers is always odd because odd numbers don't have any even factors. The GCF of any two even numbers is always even because even numbers are divisible by two and any common factors would have at least one two in common. The GCF of an even and an odd number is odd because odd numbers don't have any even factors.
Yes.
no, the GCF for 4 and 2 would be 2, which is even
No, their GCF is always odd.
The GCF will, yes.
The GCF is, yes.
Yes.
Two odd numbers always sum to an even number. Always. Two even numbers always sum to an even number, and an odd number and an even number always sum to an odd number.
Yes.
There are two truths about odd numbers. When added you get an even number... always! When multiplied you get an odd number... always!
No. The gcf of 98 and 100 is 2 .