Cicely invests 3400 dollars in an account paying an effective rate of interest of 6.4 percent. Two years later, she deposits an additional 1600 dollars. If there are no other transactions, how long will it take (from the time of the first investment) for her account balance to reach 8400 dollars? (Assume simple interest between compoundings.)
Answer = years and days.
(Note: your answer for the number of years should be a whole number, while your answer for the number of days should be given to at least 3 decimal places.)