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The series of natural number is divided ...

The series of natural number is divided into groups as follows , (1), (2,3),(4,5,6),(7,8,9,10) and so on. Find the sum of the number in the nth group is

A

`1/2[n(n^2+2)]`

B

`(n(n^2+1))/4`

C

`(2n(n+1))/3`

D

`(n^2(n+1))/2`

Text Solution

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The correct Answer is:
B
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PATHFINDER-PROGRESSION AND SERIES -QUESTION BANK
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