If the mental age of a 10 year old boy is 12, then what is his IQ?
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → 120
The Intelligence Quotient (IQ), devised by William Stern, is the mental age divided by the chronological age, multiplied by 100. Mental age (MA) is the level of a person’s intellectual development compared with people of her or his age group; chronological age (CA) is the biological age from birth.
IQ = (MA ÷ CA) × 100
MA = 12 years, CA = 10 years
IQ = (12 ÷ 10) × 100 = 1.2 × 100 = 120
The boy’s mental age is above his chronological age, so his IQ is more than 100; he is a bright child.
NCERT (2025-26): “Assessment of Intelligence … In 1912, William Stern, a German psychologist, devised the concept of Intelligence Quotient (IQ). IQ refers to mental age divided by chronological age, and multiplied by 100.…” “Assessment of Intelligence … The number 100 is used as a multiplier to avoid the decimal point. 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.…” |