effective and annual interest rate compounded monthly?

I just started my Enginnering Economic and I met this question in my quiz

PromInvest Inc. invested 5.5 million in a project ten years ago. As of
today the worth of this project is 24.7 million. What annual interest
rate has the project been earning if interest is compounded monthly?

This was how I tried to do it but the answer was wrong

24.7/5.5=4.49
120√4.49=1.012
(1.012)^12=0.162=16.2%

The other options are 14.2%, 14.8%, 15.8%, 15.2%.
Which one is correct and how to get it?