You are 30 years old and want to retire at 55. However, you do not want to start withdrawing your current retirement accounts and social security until 65. You must, therefore, fund 10 years worth of living expenses and you estimate youll need $6,250 per month during that period. If you earn 3.75% on any money invested in non-retirement accounts during the 55-64 time period and can earn 8.25% annually on your investments prior to age 55, how much must you invest at the end of each month starting next month to fund your early retirement?

Please provide exact steps on how got answer & can't use excel to find answer (have to use calculator).

Thank you!!!