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If `a_(1) , a_(2), a_(3) , cdots ,a_(n)` are in A.P. with `a_(1) =3, a_(n) =39` and `a_(1) +a_(2) + cdots +a_(n) =210` then the value of n is equal to

A

8

B

10

C

11

D

13

Text Solution

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The correct Answer is:
B
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