SOLUTION: The first term of an A.P is 7 and the sum of the first 40 terms is 1216. Find the nth term, and the 20th term.

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Question 520848: The first term of an A.P is 7 and the sum of the first 40 terms is 1216. Find the nth term, and the 20th term.
Answer by solver91311(24713) About Me  (Show Source):
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The sum of terms of an arithmetic progression is given by either:



or



Use the second one with the given information to calculate , the common difference.

Then the th term is and the 20th term is

John

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