Question

The sum of 'n' terms of a finite A P is13/2 times the sum of it's first and last terms which term would be the middle term in this A P?

Answer 1

Dear student
sum of n terms of an AP = n/2[ 1st term + nth term]
sum of n terms = 13/2 [1st term + nth term] -------- (given)

on comparing both equation
n/2[ 1st term + nth term] = 13/2 [1st term + nth term]
n/2 = 13/2
n = 13
so the number of terms are 13
hence,
the middle term will be 7th terms
( as 13 is odd number so {( 13 +1) /2} = 7 )
regards
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