The sum of 8th term of an AP is 160 while the sum of 20th is 880 fine the 43 term and the sum of the 12 term

3 answers

"sum of 8th term" makes no sense. A sum has to add two things.

Now, if you meant to say "sum of the first 8 terms" then you have
8/2 (2a+7d) = 160
20/2 (2a+19d) = 880
Then solve for a and d, then find
a + 42d
and
12/2 (2a+11d)

We're doing math here. If you can't say what you mean, then you have no hope of getting an answer that means anything.
Help me
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