For $1,000, on Who Wants To Be A Millionaire:
If four out of five dentists say that they recommend a certain kind of gum, that is exactly what percentage of dentists?
(I'm not quoting the question perfectly, but the word "exactly" was in it. Those definitely were the choices. A specific kind of gum was named but of course that's irrelevant.)
Contestant nervously giggles and says "I'm not that good at math".
Contestant answers correctly.
Okay, one comment: chances are "four out of five" in those surveys doesn't represent exactly eighty percent. Notice that you never hear, say, "nine out of eleven" or "seven out of nine" in these contexts.