Why was IQ test made?

"It was then that Alfred Binet came into picture. Binet was passionate about testing and measuring human capabilities. He tried to understand 'intelligence' through intense trial-and-error testing methods. He worked with two groups of students - average & mentally handicapped. Binet discovered that there were certain tasks that average students could handle but the handicapped students could not. Binet then calculated the normal abilities for students at each age and pinpointed how many years a student's mental age was above or below the normal.

The Paris educational authorities came across Binet's work and were largely impressed by it. In 1904, the French government commissioned him to find a method by which they could differentiate between intellectually normal and inferior children. Binet conducted the test on Paris school children and created a standard based on his data. For example, if 80 percent of 9-year-olds could pass a particular test, then success on the test represented the intelligence level of a 9-year-old.

This led to the development of the Binet Scale, also known as the Simon-Binet Scale in recognition of Theophile Simon who assisted Binet in his work. They devised a formula and calculated the IQ based upon their formula:

IQ = Mental Age/Chronological Age X 100"

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