Question

Evaluate the geometric series 1 + 6+ ... + 7776.

Answer 1

Answer:

9331

Step-by-step explanation:

clearly, r=6

So, if there are n+1 terms, 6^n = 7776

n = 5

S6 = a(r^6-1)/(r-1) = 1(6^6-1)/(6-1) = 46655/5