You plan to start saving for your son's university education. He will begin university when he turns $18$ and will need $$4,000$ then and in each of the following three years. You will make a deposit at the end of this year in an account, and an identical deposit at the end of each year, with the last deposit occurring when he turns $18.$ If an annual deposit of $$1,484$ will allow you to reach your goal, how old is your son now? Assume annually compounded $6\%$ interest in your calculation. $[$Please use financial calculator to solve this problem$]$