People with an IQ of 200, 90 ~ 1 10 belong to the normal intelligence range, those with an IQ of 120 ~ 140 are smart people, and those with an IQ of 140 or above are called geniuses. The lower the score, the worse the intelligence, and the IQ below 70 is a quantitative indicator of human intelligence level. It was put forward by German psychologist Steen in 19 12. IQ is the abbreviation of IQ, which is expressed in English. IQ is the quotient of intellectual age divided by physiological age. The calculation formula of IQ is as follows: IQ = IQ = ma÷÷÷C.A×100, and IQ represents human intelligence. The higher IQ means smarter. Physiological age refers to the actual age of a child after birth. Intellectual age or psychological age is the age measured according to intelligence measurement. Intellectual age can only represent the absolute level of intelligence, but not the intelligence level of children of different physiological ages. For example, a child is 5 years old physically and 6 years old intellectually, while b child is 10 years old and intellectually10 years old. The intellectual age of both children is older than their physiological age 1 year, so their intelligence is more difficult. Their intelligence level can be relatively compared by IQ. A child's IQ is 5/6× 100= 120, and B child's IQ is110×100 =1. From the IQ of children in A and B, it can be considered that the intelligence level of children in A is higher than that of children in B. Generally, people classify the intelligence level as follows: those whose IQ is above 140 are called geniuses; Iq 120- 140 is the best; Iq 100, 165438, 120 is the best; The IQ of 90-65438 is the best. Low ability, of which 50 ~ 70 points are idiots, 25 ~ 50 points are dementia, and 0 ~ 25 points are idiots. Intelligence has both genetic basis and environmental influence. Parents have high intelligence, and children often have high intelligence; Parents have average intelligence, while children have average intelligence; Parents are mentally defective, and children's intellectual development may be incomplete. As for the number of people with IQ above 150 in the world, it's hard to say. . It is said that the average IQ of Americans is about101; The average IQ of Japanese is about 102~ 103. The average IQ of China people is above 1 10; Jews are the nation with the highest IQ in the world, with an average IQ of 1 15. It is internationally recognized that a genius has an IQ above 130.