Demi is a 10-year-old with a mental age of 12. demi's intelligence quotient (iq) is

To calculate intelligence quotient in children, you take their mental age over their chronological age and multiply it by one hundred. So, twelve divided by 10 is 1.2, and 1.2 times one hundred is 120. Demi's intelligence quotient is 120. She is very smart, at least in the type of academics-related intelligence that is measured by IQ tests.