The GCD of given numbers is 100.
| factors of 800 are : | 1 , 2 , 4 , 5 , 8 , 10 , 16 , 20 , 25 , 32 , 40 , 50 , 80 , 100 , 160 , 200 , 400 , 800 |
| factors of 500 are : | 1 , 2 , 4 , 5 , 10 , 20 , 25 , 50 , 100 , 125 , 250 , 500 |
| factors of 300 are : | 1 , 2 , 3 , 4 , 5 , 6 , 10 , 12 , 15 , 20 , 25 , 30 , 50 , 60 , 75 , 100 , 150 , 300 |
| factors of 1000 are : | 1 , 2 , 4 , 5 , 8 , 10 , 20 , 25 , 40 , 50 , 100 , 125 , 200 , 250 , 500 , 1000 |
We see that the Greatest Common Factor = 100.