This statistical method compares the person’s actual performance with the average performance.
“The normal IQ score is still 100, meaning that the average score people get is 100. That happens because IQ test scores have a so-called “normal” distribution. In a normal distribution, most of the values cluster around the average with few values that differ significantly from it. That creates a bell shaped curve, known as the IQ bell curve, which is illustrated below.” (2)
In short the normal curve is called the visual representation of the distribution. It is used by the teachers for assigning the grades. The normal curve is also used to explain the distance between the sample and the entire