# Math Help - arithmetic seq. !

Which one of the basic functions (linear, quadratic, rational, or exponential) is related to the arithmetic sequence?
Which one of the basic functions (linear, quadratic, rational, or exponential) is related to the geometric sequence?
Give at least two real-life examples of a sequences or series. One example should be arithmetic, and the second should be geometric

2. Here's a nice example of an aritmetic sequence:

A carpenter wants to build a ladder with 9 rungs whose lengths decrease evenly from 24 inches at the bottom to 18 inches at the top.

What are the lengths of the 7 in between rungs?.

$a_{1}=24\;\ and\;\ a_{9}=18$

Use $a_{n}=a_{1}+(n-1)d$

with $n=9\;\ a_{1}=18\;\ and\;\ a_{9}=24$

24=18+8d

8d=6

Finish it up.