In USA the average I.Q. is 98 while the top one average I.Q. country is Hong Kong.
But the I.Q. distribution is given by a polinomial graph, few people with extremely low I.Q. 40~70, a lot between 70~100, some between 100~120, few between 120~140 and extremely low 140+
The normal distribution commonly works well around the middle of a distribution within the accuracy we can measure and our ability to take representative samples. Average I.Q's vary depending on the age, gander, and location of the test taker. Also, there are many forms of the tests so there can not be one form of an average I.Q.
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