SOLUTION: How many terms are there in this sequence: 12,15,18,21.......267

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Question 568427: How many terms are there in this sequence: 12,15,18,21.......267
Answer by richard1234(7193) About Me  (Show Source):
You can put this solution on YOUR website!
Subtract 9 from each term in the sequence.

3, 6, 9, ..., 258

Divide each term in the sequence by 3.

1, 2, 3, ..., 86, so there are 86 terms in the sequence. The operations we did (subtract 9, divide by 3) make it easier to count how many terms are in the sequence, without changing the number of terms in the sequence itself.