Sum of Geometric Progression

Problem
The first three terms of a geometric progression are 2x, 4x + 14 and 20x - 14. Find the sum of the first ten terms.

A.   413,633 C.   489,335
B.   498,533 D.   431,336

 

Problem
In a fund raising show, a group of philanthropists agreed that the first one to arrive would pay 25¢ to enter, and each later would pay twice as much as the preceding person. The total amount collected from all of them was \$262,143.75. How many of them paid?

Subscribe to RSS - Sum of Geometric Progression