For this case we have that by definition, the GFC or greater common factor of two numbers, is the greater number that is a factor of both numbers.
So, if we have:
[tex]8x\ and\ 40[/tex]
The GFC of both will be number 8:
[tex]\frac {8} {8} = 1\\\frac {40} {8} = 5[/tex]
The 8 is the largest number that divides both.
Answer:
8
