Find the sum of the first 25 terms of a geometric sequence where the first term is 177,147 and the common ratio is .

Here's the relevant formula:

                                  1 - r^n
nth partial sum = a* ------------
                                    1 - r
                                                              1 - r^25
Here, the 25th partial sum is 177147 *-------------
                                                                1 - r

Unfortunately, you haven't yet shared the value of the common ratio.  Find that value and substitute it for r in the above expression.