A community for students.
Here's the question you clicked on:
 0 viewing
Fanduekisses
 one year ago
What am I doing wrong?? pls help!
Fanduekisses
 one year ago
What am I doing wrong?? pls help!

This Question is Closed

Fanduekisses
 one year ago
Best ResponseYou've already chosen the best response.0I came up with this...?\[\sum_{n=0}^{4}27(\frac{ 1 }{ 9 })^{n}\]

Fanduekisses
 one year ago
Best ResponseYou've already chosen the best response.0so I'll have to find the sum then square that???

Fanduekisses
 one year ago
Best ResponseYou've already chosen the best response.0idk I thought I got it but then I checked the answer key and It wasn't :(

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.5You square first, then sum \[\Large (A+B)^2 \ne A^2 + B^2\]

Koikkara
 one year ago
Best ResponseYou've already chosen the best response.1hmm, i don't remember how to do it that way... I tried this way, The area of the 1st square = \(27^2 \) After \(÷ 9 \) the area of the center square would be \((27^2)/9\) If repeat once, the area would be\( ((27^2)/9) /9 \) Then if repeat three times, the area would be \((27^2)/(9^4)\)...\(right~~ ?\)

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.5and also, 27^2 is not included because the whole 27x27 square isn't shaded

Fanduekisses
 one year ago
Best ResponseYou've already chosen the best response.0wait, still something weird...

Fanduekisses
 one year ago
Best ResponseYou've already chosen the best response.0the answer should be 273.88

Koikkara
 one year ago
Best ResponseYou've already chosen the best response.1@Fanduekisses i tried this way, In the first step it is applied to an area of 27². and for The 2nd Box, (1/9) of the area to which it is applied. now looking at the second step to the remaining area: 27²(1/9)27² = (8/9)27². Let us consider, previous unshaded area as A, then an area (1/9)A is added to the shaded area and A(1/9)A=(8/9)A is left still unshaded. So the shaded areas are: (1/9)27² + (1/9)(8/9)27² + (1/9)(8/9)²27² + (1/9)(8/9)³27² = ? Alternatively, the shaded areas form a Geometric Sequence with a common ratio of (8/9). So the shaded area after 4 steps is just: 27²  (8/9)⁴27² = ? i think so...

Fanduekisses
 one year ago
Best ResponseYou've already chosen the best response.0I thought I had to us sum of finite geometric series or so, that's what the chapter is about.

Fanduekisses
 one year ago
Best ResponseYou've already chosen the best response.0So the common ratio is actually 8/9? not 1/9?

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.5hmm well I thought it was 8/9, but I keep getting this S = a*(1r^n)/(1r) S = 81*(1(8/9)^6)/(18/9) S = 369.406035665294 but it's not the answer your book is saying

Fanduekisses
 one year ago
Best ResponseYou've already chosen the best response.0:( so confusing. The chapter was on geometric sequences and series.

Fanduekisses
 one year ago
Best ResponseYou've already chosen the best response.0I thought the common ratio was 1/9.

Fanduekisses
 one year ago
Best ResponseYou've already chosen the best response.0if 273.88 is the area of the shaded region, then the sum would have to be around 16?

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.5each smaller square is 1/9 of the area of the previous bigger square but there are 8 smaller squares added each time, so that's why we get 8*(1/9) = 8/9

Fanduekisses
 one year ago
Best ResponseYou've already chosen the best response.0How is it related to the topic, geometric series and sequences then? how would I use the summation stuff?

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.5you started off with the first term of 81. The largest square area in the center then you add on 8 squares each 3*3 = 9 square units there are 8 of these smaller squares, so 8*9 = 72 square units is added on first term = 81 second term = 72 common ratio = 72/81 = 8/9

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.5this pattern repeats where the next term (the sum of the smallest squares in figure 3) is 64 64/72 = 8/9 and so on

Fanduekisses
 one year ago
Best ResponseYou've already chosen the best response.0ohhhh my God, I was focusing more on the side than on the area!

Fanduekisses
 one year ago
Best ResponseYou've already chosen the best response.0So using the sum of finite geometric series: \[\frac{ 27(1(\frac{8 }{ 9 })^4 )}{ 1\frac{ 8 }{ 9 } }= 273.88\]

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.5first term isn't 27

Fanduekisses
 one year ago
Best ResponseYou've already chosen the best response.0haha yeah I meant 81

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.5and you're going to have n = 6 because the problem is showing 3 cases (n=1, n=2, n=3) already and they say repeat the pattern 3 more times

Fanduekisses
 one year ago
Best ResponseYou've already chosen the best response.0ohh ok thanks so much!
Ask your own question
Sign UpFind more explanations on OpenStudy
Your question is ready. Sign up for free to start getting answers.
spraguer
(Moderator)
5
→ View Detailed Profile
is replying to Can someone tell me what button the professor is hitting...
23
 Teamwork 19 Teammate
 Problem Solving 19 Hero
 Engagement 19 Mad Hatter
 You have blocked this person.
 ✔ You're a fan Checking fan status...
Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.