Answer :
The IQ of a 6-year-old child with a mental age of 9 is calculated to be 150, using the formula IQ = (mental age \/ chronological age) \\times 100. Therefore, the correct option is c) 100.
The IQ of a 6-year-old child with a mental age of 9 can be calculated using the formula IQ = (mental age \\/ chronological age) \\times 100. According to this formula, we would calculate the child's IQ by dividing the mental age (9) by the chronological age (6) and then multiplying by 100.
So, the calculation would look like the following: (9 \\div 6) \\times 100 = 150. Therefore, the correct answer is d) 150. This high IQ score indicates that the child's mental capabilities are quite advanced compared to the average intellectual performance expected at their chronological age. Therefore, the correct option is c) 100.
