Question

the sum of n terms of a finite A.P is 13/2 times the sum of its first and last terms which would be the middle tem in this A.P? give answer fastly​

Answer 1

Answer:

7th term

Step-by-step explanation:

sum of n terms of AP= Sₙ=n/2 (2a+(n-1)d)

first term = a

last term = a+ (n-1)d

first term + last term = a + a + (n-1)d = 2a+(n-1)d

the sum of n terms of a finite A.P is 13/2 times the sum of its first and last terms

n/2 (2a+(n-1)d) =13/2 (2a+(n-1)d)

on comparing these two

n=13

so (n+1)/2=14/2=7th term is the middle term