Hello, Keith!

Wrong formula!I am asked to use this formula: Sn = a/(1-r) for |r|<1 to solve this problem:

. . (1.07) + (1.07)^2 + (1.07)^3 + ...+(1.07)^60

That formula is for aninfinitegeometric series.

. . This series is not infinite; it has only 61 terms.

For a geometric series withnterms, the formula is:

. . . . . . . . . . . 1 - r^n

. . . S_n . = . a --------

. . . . . . . . . . . . 1 - r