Please explain how this is down I tried a few different ways and I don't know which way is correct especially because each way gave me a different answer.

3. Suppose a bank offers an annual interest rate of 3% compounded monthly. If you invest $10,000 today, how long will it take for the account to hold $20,000? Note: On #3 you should round your answer up to the nearest month. The following conversions will help: 2 1 month ~ 0.083 year 2 months ~ 0.167 year 7 3 months = 0.25 year 4 months ~ 0.333 year 5 months ~ 0.417 year 6 months = 0.5 year 7 months ~ 0.583 year 8 months ~ 0.667 year 9 months = 0.75 year 10 months ~ 0.833 year 11 months ~ 0.917 year 12 months = 1 year