Final answer:
A five-year-old child with a mental age of four would have an IQ of 80 on the Stanford-Binet scale. This score is determined by dividing the mental age by the chronological age, and then multiplying by 100.
Step-by-step explanation:
The subject question deals with calculating an IQ score using the Stanford-Binet Intelligence Scale. To find the IQ of a five-year-old child with a mental age of four, we use the formula:IQ = (Mental Age / Chronological Age) × 100 For this calculation, Mental Age is 4, and Chronological Age is 5, so:IQ = (4 / 5) × 100 = 0.8 × 100 = Therefore, the main answer to the student's question is: a) 80.In conclusion, a five-year-old child who scores at a mental age of four on the Stanford-Binet test would have an IQ score of 80, which is below the average IQ score of 100, representing one standard deviation below the mean in the context of a normal distribution. This score is calculated by the ratio of the mental age to the chronological age, multiplied by 100.