Question

Find the sum 11+13+15+17+.......35

Answer 1

Answer:

It's only a basic problem of Mathematics of

Arithmetic Progressions

Step-by-step explanation:

We have, A.P= 11,13,15,17......35

therefore,

A= 11 (first term)

D= 13-11=2 (common difference)

an= 35 (last term)

therefore,

an= a+(n-1)d

35= 11 +(n-1)2

24=2n-2

13=n

therefore

Sn= n/2(2a+(n-1)d)

Sn= 13/2(22+(12)2)

Sn= 13/2(46)

Sn=13×23

therefore,Sn=299

Hope this helps...!!!

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