Consider a geometric progression with common ratio 4. If the sum of the first 6 terms is 6825, what is the initial term?
Use the GP formula: Sum =F x ((1 - R^N) / (1 - R)) 6825=F x ((1 - 4^6) / (1 - 4)) 6825=F x ((1 - 4096) / (- 3)) 6825=F x ((- 4095) / ( - 3)) 6825=F x 1365 F =6825 / 1365 F = 5 - First term of the GP
