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If a(1), a(2), a(3),…….,a(20) are in AP ...

If `a_(1), a_(2), a_(3),…….,a_(20)` are in AP and `a_(1) + a_(20) = 45`, then `a_(1) + a_(2) + a_(3)+……+a_(20)` is equal to

A

90

B

900

C

350

D

450

Text Solution

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The correct Answer is:
D
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