KingJ
What is the sum of the arithmetic sequence 8, 14, 20 …, if there are 24 terms?



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adnanchowdhury
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S = 2a + (n1)d
Where a = first number in sequence, n is nth term you are looking for and d is the common difference.

adnanchowdhury
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sorry, it should be:
S = n/2( 2a + (n1)d)

Mertsj
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\[s _{n}=\frac{n}{2}(a _{1}+a _{n})\]
To find the 24th term use:
\[a _{n}=a _{1}+(n1)d=8+(241)6=146\]
\[s _{n}=\frac{24}{2}(6+146)\]
\[s _{n}=1824\]

Mertsj
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There. I think I finally got it right.

KingJ
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THANK YOU

Mertsj
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yw

cinar
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dw:1328989953105:dw

cinar
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1848

cinar
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you put a1=6 but it is 8

cinar
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dw:1328990276982:dw

malice
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The correct answer is 1848! Tyy!!