Asked by sonaisha | 9th Mar, 2009, 11:56: PM

Expert Answer:

we'll be using the fact that the sum of n terms of an A.P. with first term=a and

 common difference =d


 n/2[ 2a+(n-1)d]

Pl check if  there anyhting else given in the question regarding the two  A.Ps.Do get back to us.


Answered by  | 10th Mar, 2009, 12:17: PM

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