There was a "Brain Games" episode on this. I think the reason many people say "Red Hammer" is because your brain was already busy with math, it doesnt put much thought into the answer. My guess would be that "red" is the most famous, or bold(or something like that) color so your brain jumps to that as a quick answer, and same for the hammer.
I chose a red rake. I had just gotten done using one when I did this the other day. If I had allowed myself to think I probably would have chosen green and a more imaginative tool. I think these things are interesting. People keep it simple when they rush so I think the answer will tend to be something they have experienced recently or something that is ingrained. When I asked my wife to quickly name a color and tool, she was using a web page that had a lot of blue on it. She said blue screwdriver. Red and blue are short names and the first ones we learn as kids. You are also probably sitting near something that is red or blue. A hammer is similar. We were all pounding on things as babies long before we figured out any other tools. I would say the tool I use most is a screwdriver. I was trying to Google a bit for Family Feud answers and so forth and found these: http://www.familyfeudinfo.com/question.php?id=2762 http://www.thetoptens.com/top-ten-favorite-colors/
