Mr Pham's retirement account has 410 000 dollars. Let's put to a situation that he's not withdrawing from his account for several years, and this earns an annual interest of 3.85%.Let's find out how much will he earn: => 3.85% = 3.85% / 100% = .0385 => 410 000 * 0.0385 = 15 785 dollars.Mr, Pham will earn around 15 785 dollars in every year for 2 years he will earn times 2 of this amount that will be added to his retirement amount. => 15 785 dollars * 2 = 31570 dollars for 2 years and so on.