Hello there!
To find the GCF, we must list all the factors and then just spot the greatest factor.
28: 1, 2, 4, 7, 14, 28.
210 1, 2, 3, 5, 6, 7, 10, 14, 15, 21, 30, 35, 42, 70.
So 14 is the GCF. Hope this helps you!
~Just a felicitous girlie
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