I know you say quot;six by six foot rugquot; or quot;six sq.foot rugquot; but which of the above is correct?
You're using it as an adjective, a six-foot rug. It'll be easier to give more examples than to describe the rule. A drive of ten miles is a ten-mile drive. A baby that weighs eight pounds is an eight-pound baby. A building with six stories is a six-story building. Etc.
Just another one of those strange English constructions. If I were saying it, I would say that is a six foot by six foot rug, but I could also say that rug measures six feet by six feet, and they are not interchangeable. In other words, I would never say that is a six feet by six feet rug, and it would be unusual for me to say that rug measures six foot by six foot, though some people might use the latter construction. And just to complicate things, it is always a 36 square foot rug (not a 36 square feet rug), but you would describe it as having 36 square feet (not 36 square foot).
Six by six foot, for some reason. It wouldn't be six sq. foot, it would be 36 sq. foot.
Since feet is plural of foot and you have more than one, I would guess that the latter is correct. But who knows for sure the way we use English is screwed up.
