Question

find the middle term of the A.P:6, 13, 20,...........216​

Answer 1

6,13,20,...............216

a=6

d=7

The formula to find is

Tn=a+(n-1)d

216=6+(n-1)7

216=6+7n-7

216=7n-1

217=7n

n=217/7

n=31

to find middle term in AP the formula is when the given number's are odd

(n+1)/2.

now it is

(31+1)/2

=16

and here 16 term is middle in the AP

the 16=111.

I hope you got the answer.

Answer 2

middle term if ap is 111.