Question 1044785
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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 = {{{(212+12)/8}}} = 28.

Hence, n = 28 + 1 = 29.

<U>Check</U>.  -12 + 8*(29-1) = -12 + 8*28 = 212.  Correct !

<U>Answer</U>.  212 is the 29-th term.
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