If a person’s chronological age is 15 and IQ is 120, then what would be the mental age of that person?
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → 18
Intelligence Quotient (IQ) is mental age divided by chronological age, multiplied by 100. Here the IQ and the chronological age are given, so the mental age is found by working the formula backwards.
Given: chronological age (CA) = 15 years, IQ = 120
IQ = (MA ÷ CA) × 100
120 = (MA ÷ 15) × 100
MA = (120 × 15) ÷ 100 = 18 years
When the mental age is more than the chronological age, the IQ is more than 100, so an IQ of 120 must go with a mental age greater than 15.
NCERT (2025-26): “Assessment of Intelligence … In 1908, when the scale was revised, they gave the concept of Mental Age (MA), which is a measure of a person’s intellectual development relative to people of her/his age group. A mental age of 5 means that a child’s performance on an intelligence test equals the average performance level of a group of 5-year olds. Chronological Age (CA) is the biological age from birth. A bright child’s MA is more than her/his CA; for a dull child, MA is below the CA.…” “…In 1912, William Stern, a Ger man psychologist, devised the concept of Intelligence Quotient (IQ). IQ refers to mental age divided by chronological age, and multiplied by 100.…” “…When the MA equals the CA, the IQ equals 100. If MA is more than the CA, IQ is more than 100. IQ becomes less than 100 when the MA is less than the CA.…” |