SOLUTION: The 12th term of an A.P is -41 given that the first term is 3 find the 20th term

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Question 1165610: The 12th term of an A.P is -41 given that the first term is 3 find the 20th term
Answer by ikleyn(52788) About Me  (Show Source):
You can put this solution on YOUR website!
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There are 12-1 = 11 equal gaps between -41 and 4, each of the size of  %284+-+%28-41%29%29%2F11 = 44%2F11 = 4.


So the common difference is -4 and the 20-th term is  3 - 4*(20-1).


I leave this simple calculation to you.

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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
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    - ALGEBRA-II - YOUR ONLINE TEXTBOOK.

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


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Free of charge online textbook in ALGEBRA-II
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