The research is concerned with the development of a mathematical model for estimating Intelligent Quotient of human above 65years. The model was optimized to know whether we have maximum or minimum human IQ level. However, the optimization result showed a saddled point which indicates that there is no minimum or maximum human IQ in life. This result implies that there is no particular IQ level that any human above 65years cannot attain when there is an enabling environment for adult education and other adult related trainings geared towards sharpening IQ skills of our retired and aged people. Similarly the IQ model was also validated with data from real life. And the outcome of the validation gave a correlation coefficient of 0.990405. This implies that our model is approximately 99% in agreement with real life data used, thus shows that the model is a standard measure for estimating IQ of human above 65years.