SOLUTION: find the 24th term of the arithmetic sequence whose common difference is d=2 and whose first term is -30

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Question 1200509: find the 24th term of the arithmetic sequence whose common difference is d=2 and whose first term is -30
Found 2 solutions by ikleyn, greenestamps:
Answer by ikleyn(52790) About Me  (Show Source):
You can put this solution on YOUR website!
.

Use the general formula  a%5Bn%5D = a%5B1%5D + (n-1)*d,


which gives  a%5B24%5D= -30 + (24-1)*2 = -30 + 46 = 16.   ANSWER

Solved.

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For introductory lessons on arithmetic progressions see
    - Arithmetic progressions
    - The proofs of the formulas for arithmetic progressions
    - Problems on arithmetic progressions
    - Word problems on arithmetic progressions
in this site.

Also,  you have this free of charge online textbook in ALGEBRA-II in this site
    - ALGEBRA-II - YOUR ONLINE TEXTBOOK.

The referred lessons are the part of this online textbook under the topic "Arithmetic progressions".


Save the link to this textbook together with its description

Free of charge online textbook in ALGEBRA-II
https://www.algebra.com/algebra/homework/complex/ALGEBRA-II-YOUR-ONLINE-TEXTBOOK.lesson

into your archive and use when it is needed.



Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!


You should know how to use the formal algebra to find the answer to a question like this.

But the basics of arithmetic sequences are so simple you should understand how to get the answer to a problem like this informally, with simple mental arithmetic.

To find the 24th term of the sequence, you take the first term and add the common difference 23 times:

ANSWER: -30 + 23(2) = -30+46 = 16