Find the 84th term of the arithmetic sequence

Find the 84th term of the arithmetic sequence 18, 31, 44, ……

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The arithmetic sequence is starting with 18, and then you are adding 13, eighty-three times.
In other words, the first term is 18 and the common difference is 13.

To find the 84th term:

18 + 13(83) {start with 18 (the first term) and add 13 eighty-three times}
= 18 + 1079 {multiplied 13 by 83}
= 1097 {added}

The 84th term is 1097.

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