Answer:
Hence, the sum of the geometric series is:
259
Explanation:
We are given a geometric series as:

i.e. we are asked to fnd the sum of first four terms of the geometric series with first term as 1
Since, the series is:

Also, the common ratio of the series is: r=6
Since, each of the term of the series is 6 times it's preceding term.
Also we know that sum of a finite geometric series with n-terms and common ratio r is calculated by the formula:

Here we have: a=1 and r=6 and n=4
Hence,

Hence, the sum of the series is:
259