Q: find the sum of all common prime factors of 51 and 204
so I found 1, 3, 17 for the common prime factors of those two numbers. but does "1" count and a common prime factor?
my answer: 20 or 21??
That "I misread the post" is an understatement: I must have been high, drunk or both when I dealt (?) with it. This is funny since I do no drugs at all and only drink alcoholic beverages once in a while, and also that in very minimal quantities.
I hope the OP didn't get too confused with my nonsense.