Mental age of 10 year old boy is 12 years. Find his I Q.

Question

Accepted Answer

The correct option is (2):

The question asks us to calculate the Intelligence Quotient (IQ) of a 10-year-old boy with a mental age of 12 years. The formula for IQ, originally developed by William Stern and later popularized by Lewis Terman, is (Mental Age / Chronological Age) * 100. In this case, the Mental Age (MA) is 12 years, and the Chronological Age (CA) is 10 years. Plugging these values into the formula, we get (12 / 10) * 100 = 1.2 * 100 = 120. Therefore, the boy's IQ is 120. An IQ of 120 indicates above-average intelligence. This formula is a fundamental concept in the study of intelligence and psychological assessment.

The incorrect option is (1): 84

This option would imply an IQ calculation of (8.4 / 10) * 100 or some other incorrect values. If a child has an IQ of 84, it indicates below-average intelligence, and it does not align with the provided mental and chronological ages.

The incorrect option is (3): 110

An IQ of 110 would result from a calculation such as (11 / 10) * 100. While 110 is above average, it does not match the given mental age of 12 and chronological age of 10. It suggests a mental age closer to the chronological age.

The incorrect option is (4): 100

An IQ of 100 signifies average intelligence, meaning the mental age and chronological age are equal. If the boy's IQ were 100, his mental age would be 10 years, not 12 years. This option would be correct if the mental age was 10, but not with a mental age of 12.