# Solution - Sum of First n Terms of an AP

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ConceptSum of First n Terms of an AP

#### Question

If the sum of the first n terms of an A.P. is 1/2(3n2 +7n), then find its nth term. Hence write its 20th term.

#### Solution

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#### Reference Material

Solution for concept: Sum of First n Terms of an AP. For the course 8th-10th CBSE
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