Puzzle #4 I'd guess the answer has to deal with averages.
I would pick 8, 4, 1.
Average age for sixty one pound boy is 8.
Since we might have to rule out twins as being the oldest as he said "oldest son" and not "one of my oldest sons."
Presuming the average ages of the two men would be relatively close.
Then we move onto the possibilities of the ages to determine the possible age range of the two men.
8x4x1=32, 8x3x2=48, on average, what would be the age that the average father would have his first baby? 24 or 40?
Dealing with averages, I'd say 8, 4, and 1 as the ages of the boys.
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Puzzle #3
Yellow---------Blue------Red-------Green-----White
Norwegian---Dane-----Brit--------German---Swede
Dunhill--------Blends---PallMall----Prince-----Bluemeister
Water--------Tea--------Milk--------Coffee----Beer
Cats----------Horse-----Birds-------Fish-------Dogs
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Puzzles 1 & 2 I couldn't figure out until the solutions were posted.
Then it was
"Of Coarse!!"
Man, these made me think!!
Great thread!!!
Edited to add lines to #3 to keep the order visually