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If the sum of first n terms of an AP 2,4...

If the sum of first n terms of an AP 2,4,6, . . . 240, then the value of n is

A

14

B

15

C

16

D

17

Text Solution

Verified by Experts

The correct Answer is:
B
`(n)/(2)[2xx2+(n-1)xx2]=240`
`impliesn(2+n-1)=240`
`impliesn(2+n-1)=240`
`impliesn(n+1)=15xx16impliesn=15`
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