What is the value of s4 for infinity 2/3(-1/5) n-1

Now, bearing in mind that for an infinite serie, when the "common ratio" or "r" is a fraction between 0 and 1, namely 0 < | r | < 1, the sum of it is convergent, namely it reaches a fixed value.in this case, notice the geometric sequence structrue, thus r = -⅕, and since 0 < | -  ⅕ | < 1, then this sequence is indeed convergent.