Let

where we assume |r| < 1. Multiplying on both sides by r gives

and subtracting this from
gives

As n → ∞, the exponential term will converge to 0, and the partial sums
will converge to

Now, we're given


We must have |r| < 1 since both sums converge, so


Solving for r by substitution, we have


Recalling the difference of squares identity, we have

We've already confirmed r ≠ 1, so we can simplify this to

It follows that

and so the sum we want is

which doesn't appear to be either of the given answer choices. Are you sure there isn't a typo somewhere?
She would have to get 78.75 dollars every week to get the camera.
Which question? The picture is black
A regular hexagon has sides that are all congruent and angles that all measure 120 degrees. This means the angles of a regular hexagon add up to 720 degrees. ... An irregular hexagon has sides that are not the same measurement and can have points facing inward as well as outward.
5 1/4 as a decimal is 5.25
this is because 1/4 is equal to 25/100