Assume the total cost of college education will be $$390,000$ when your child enters college in $18$ years. You presently have $$64,000$ to inyest. What annual rate of interest must you earn on your investment to cover the cost of your child's college education?

Note: Do not round intermediate calculations and enter your answer as a percent rounded to $2$ decimal places, e$.$g$.,32\mathrm{.}16.$

Annual rate