Question

Find the middle term of the ap with 17 terms whose 5th term is 23 and the common difference is -2

Answer 1

Solution:-
Given: 5th term = 23 and common difference = - 2
So, 
a₅ = 23
= a + 4d = 23
a + (4 × - 2) = 23
a = 23 + 8
a = 31
So, the first term is 31
There are total 17 terms in the given AP, so the middle term is a₉
So, 
a₉ = a + (n-1)d
a₉ = 31 + (9 - 1) (- 2)
= 31 + (8 × -2)
= 31 - 16
a₉ = 15
So, the middle term is 15
Answer.

Answer 2

Answer:

Step-by-step explanation:

Given: 5th term = 23 and d = - 2

a₅ = 23

= a + 4d = 23

a + (4 × - 2) = 23

a = 23 + 8

a = 31

So, the first term is 31

There are total 17 terms in the given AP, so the middle term is a₉

So, 

a₉ = a + (n-1)d

a₉ = 31 + (9 - 1) (- 2)

= 31 + (8 × -2)

= 31 - 16

a₉ = 15

answer is 15