..

- anonymous

..

- Stacey Warren - Expert brainly.com

Hey! We 've verified this expert answer for you, click below to unlock the details :)

- katieb

I got my questions answered at brainly.com in under 10 minutes. Go to brainly.com now for free help!

- kanwal32

(2/3)^n-1

- kanwal32

to infinite or 4

- kanwal32

no i am asking till where we have to find infinite or 4

Looking for something else?

Not the answer you are looking for? Search for more explanations.

## More answers

- anonymous

@kanwal32

- anonymous

you mean this?

- sdfgsdfgs

yes, thats what he is asking. But do u understand the solution given in the old post? u can simply substitute 3/2 by 2/3 to get ur ans...

- sdfgsdfgs

there is a formula given in the old post on how to calculate the sum....did u see it?

- anonymous

I did, but it's pretty confusing, could you start me out?

- sdfgsdfgs

u need to understand the 3 terms used in the formula: a, R and n
a is the initial term in the series so in this case, it is equal to
\[(\frac{ 2 }{ 3})^{1-1} \]
=1
ok?

- anonymous

Okay.

- sdfgsdfgs

R is the common ratio...so what is the ratio between the first and second term in this series?
Basically what u get if u divide the second term by the first term? u already know the first term, a, is 1...

- sdfgsdfgs

nope, first term is 1....what is the second term - when n=2....

- sdfgsdfgs

|dw:1434612184951:dw|

- sdfgsdfgs

no, ignore the part that I scribbled out...whatever is left, substitute n=2 and what will u get?

- anonymous

I think it is 3

- sdfgsdfgs

\[(\frac{ 2 }{ 3 })^{(2-1)}\] = 2/3
So that is R in the formula ok?

- sdfgsdfgs

n is simple and equal to 4 in this case.
So for the formula in the last post, use the following:
a=1
R=(2/3)
n=4
to calculate the sum. Good luck!

- anonymous

(2/3) (2 - 1) is 2/3. now what? @sdfgsdfgs

- sdfgsdfgs

What is the formula to get the sum from the old post?

- sdfgsdfgs

See it here:
http://assets.openstudy.com/updates/attachments/4fb88e44e4b05565342dc675-kelly_01-1337495416339-geometric_sequence_17.gif

- anonymous

oh okay..

- sdfgsdfgs

a=1
R=2/3
n=4
Calculate S which is ur ans.

- sdfgsdfgs

Put in the values we found for a, R and n....

- anonymous

where would a go?

- sdfgsdfgs

It IS a simple question but I think u have skipped ur study material related to the geometric series. Otherwise u should not have so much trouble :(

- sdfgsdfgs

not funny :( sorry it is late...I need to go soon.
put the values into the last line here: http://assets.openstudy.com/updates/attachments/4fb88e44e4b05565342dc675-kelly_01-1337495416339-geometric_sequence_17.gif

- sdfgsdfgs

sorry to hear about ur health problem but u really need to understand the geometric series first before u can solve problems like this....

- sdfgsdfgs

Correct! It is
\[S = \frac{ (1-(\frac{ 2 }{ 3 })^4 )}{ 1-\frac{ 2 }{ 3 } }\]

- sdfgsdfgs

We work it out this time because u found the old post. But you should read up geometric series before taking on more problems like this one.

- anonymous

im right there and i kind of understand it a bit now..

- sdfgsdfgs

try it again - 65/16 is not the right ans.

- anonymous

okay one sec..

- sdfgsdfgs

sorry i need to go now....65/27 is the right ans. good luck!

Looking for something else?

Not the answer you are looking for? Search for more explanations.