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 Question from paris, a student: find the twenty-fifth term of an arithmetic sequence whose first term is 12 and whose common difference is -6

Hi Paris,

To get from ay term in an arithmetic sequence you add the common difference. Thus in your arithmetic sequence the first tem is $12$ so the second term is $12 + (-6) = 6$ and the third term is $12 + 2 \times (-6) = 0.$ How many times do you need to add $-6$ to get to the twenty-fifth term? What is the twenty-fifth term?

Penny

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