The amount of the tip is 12%
assuming 
Then the column values for base five here are
5³ 5²

We can get 1 × 5³ = 125 → 219 - 125 = 94
We can get 3 × 5² = 75 → 94 - 75 = 19
We can get 3 x
→ 19 - 15 = 4
and 4 = 4 × 
Thus
= 
As a check
(1 × 125 ) + (3 × 25 ) + (3 × 5 ) + 4 = 219
Answer:
if you want the base and the height you have to give me number or do you want the formula ?
An alternating series

converges if

is monotonic and

as

. Here

.
Let

. Then

, which is positive for all

, so

is monotonically increasing for

. This would mean

must be a monotonically decreasing sequence over the same interval, and so must

.
Because

is monotonically increasing, but will still always be positive, it follows that

as

.
So,

converges.