Question 1044785: The first three terms of an arithmetic sequence are -12, -4, and 4. Which term is 212 ? Found 3 solutions by Alan3354, ikleyn, MathTherapy:Answer by Alan3354(69443) (Show Source):
You can put this solution on YOUR website! The first three terms of an arithmetic sequence are -12, -4, and 4. Which term is 212 ?
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Term n = -12 + 8*(n-1)
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Term 1 = -12
Term 2 = -4
Term 3 = +4
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Term 212 = -12 + 8*211 = 1676
You can put this solution on YOUR website! .
The first three terms of an arithmetic sequence are -12, -4, and 4. Which term is 212 ?
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212 = -12 + 8*(n-1). (1)
You are asked to find n.
From (1) n-1 = = 28.
Hence, n = 28 + 1 = 29.
Check. -12 + 8*(29-1) = -12 + 8*28 = 212. Correct !
Answer. 212 is the 29-th term.
