Sum of the first nth term of Series in Javascript

This problem took me a little time to understand due to the fact that it is very math intensive. For the most part this problem wants you to take in a number that is over 0. As the number gets bigger there are supposed to be more integers that you add to the solution. To start off this this solution would greatly benefit from using a for loop. I knew i needed a variable to keep track of the sum that we are trying to find so that was the first thing that I defined. The hard part was to figure out how to increment the denominator of the fraction that we are adding. After a while I figured out the denominators were equal to the number time 3 and then plus one. After that I just had to figure out how to return the solution with just two decimal points, and that just took a quick google search to find the .toFixed method would work. Here is my solution.