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 Question from Juliette, a student: Find X when x, 1/2x + 7, 3x -1 are consecutive terms of an arithmetic sequence.

Hi Juliette,

If $a, b \mbox{ and } c$ are three consecutive terms in an arithmetic sequence then the middle term is half way between the other two on the number line. In your situation that means that $\frac12 x + 7$ is the average of $x\mbox{ and } 3x - 1.$ Solve for $x.$

Penny

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