According to Resing and Blok (2002),
as with average IQ score, there is usually standard deviation of 15 as a measure of dispersion, which means that the average score (100) is 15 points deviated either positively or negatively so that the average score in the entire populaton and within the IQ curve itself is not left to chance.
That is, (100 – 15 = 85) and (100 + 15 = 115) as depicted in the image above.
There are diverse sorts of IQ tests with each having their own particular scale. Subsequently, two individuals who have an IQ of 100 on various scales may not really have a similar intelligence level. However, all tests and scales utilize 100 as the IQ of a man of normal intelligence.
Since the normal IQ is said to be 100, subsequently anything over 100 is considered as better than expected and beneath 100 as below normal. IQ below 70 is taken as that of a dullard or mentally retarded individual. IQ 140+ is for the most part considered as that of a genius.
Why you don’t want to dwell on 100 IQ
A great many people, if sufficiently intelligent beyond average, would notice that a man of 100 IQ to be somewhat duller than what they are used to.
Unfortunately, in a present day modernized society, 100 IQ is scarcely ‘sufficient’ to carry on with a typical agreeable life any longer as Americans and Chinese have a tendency to be IQ-fixated.
Presently, recall, IQ is a composite of a few domains of intelligence; in light of the fact that your IQ is 100 doesn’t mean you are 100 in everything. In case you are unusually terrible at a specific subsection of the test, it can drag your score down to a degree that the number doesn’t mirror your intelligence decently. In this case, IQ would be just fun, and baseless.
Resing, W.C.M., & Blok, J.B. (2002). The classification of intelligence scores. Proposal for an unambiguous system. The psychologist, 37, 244-249.