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What are the next three terms in the arithmetic sequence 15.8, 14.6, 13.4, and 12.2.
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In an arithmetic sequence, we add a constant to each term to get the following term.
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And that constant that we add we call the common difference.
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And the way that we can find the common difference is we can take a term and then subtract the previous term from it.
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So if we take 14.6 and subtract the previous term 15.8, we get negative 1.2.
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So that means to get the next term, we need to take 14.6 and subtract 1.2, and that would indeed get us 13.4.
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And if we would take 13.4 and subtract 1.2, we get 12.2 which was our next term.
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So to find the next three terms in this arithmetic sequence, we need to take 12.2 and subtract 1.2.
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And we get 11.
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And now to get the next term, we take 11 and subtract 1.2.
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And we get 9.8.
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And lastly, we take 9.8 and subtract 1.2 again.
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And we get 8.6.
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So the next three terms in this sequence would be 11, 9.8, and 8.6.