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anonymous
 one year ago
I don't know why I am getting the wrong answer, please help!
16. The first term of an arithmetic progression is 6 and the fifth term is 12. The progression has n terms and the sum of all the terms is 90. Find the value of n.
I will post a picture of my working out.
anonymous
 one year ago
I don't know why I am getting the wrong answer, please help! 16. The first term of an arithmetic progression is 6 and the fifth term is 12. The progression has n terms and the sum of all the terms is 90. Find the value of n. I will post a picture of my working out.

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anonymous
 one year ago
Best ResponseYou've already chosen the best response.0The correct answer is 8

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1i got 8 !! :D now wait a sec i'll check ur work

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1http://prntscr.com/8ig2duis it 45/n ??

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0The screenshot didn't work

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0But in the beginning I did get 45/n

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1okay so at left side is it 45/n it's a 2nd row

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Oooh...I combined 1/2 n and 90. not like terms so I cant do that right?

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1it's \[\frac{ 3 }{ 2}n = \frac{3n}{2}\] n isn't at the denominator

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1ye first combine 123/2

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1\[\huge\rm 90=\frac{ n(\color{Red}{12}+\frac{ 3 }{ 2 }n\color{Red}{\frac{ 3 }{ 2} })}{ 2 }\] like terms

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Ok. I will try again quickly.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0I got 7.46, Did I lose some accuracy somewhere or is that what I am meant to get?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Awwww. Oh well. Ok should i post my working out again?

welshfella
 one year ago
Best ResponseYou've already chosen the best response.0a + 4d  a = 4d = 12  6 = 6 so d = 3/2

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1first multiply both sides by 2 \[\huge\rm 90 · 2=\frac{ n(\color{Red}{12}+\frac{ 3 }{ 2 }n\color{Red}{\frac{ 3 }{ 2} })}{ 2 }· 2\] combine 123/2 and then distribute parentheses by n

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0the n=9 is from the other equation

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Oh. I think I forgot that its over 2

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1no you didn't you distributed the parentheses by (1/2)n

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0I'm sorry, I don't really understand whaI did wrong?

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1i know what happened t o12.25 ?? check ur 6th and 7th row

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0I was making a perfect square

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1wdw:1442760681511:dw you should add (b/2)^2 to both sides

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Oh!! I forget to do that a lot >:/ Ok, third time lucky. Trying again.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Aaaaand I am finally getting it right!

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Thank you for your patience and for helping me so much! :D

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1my pleasure &GREAT JOB!! i like how u posted ur work :=) that was super cool!
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