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If the sum of a certain number of terms of the AP `25,22,19...` is 116. Find the last term.

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Let the sum of n terms of the given A.P. be` 116. `
`S_n=n/2[2a+(n-1)d]`
Here, `a = 25` and `d = 22 – 25 = – 3`
Then, `S_n=n/2[2 times 25+(n-1)(-3)]`
`=> 116=n/2[50-3n+3]` ...
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