Question

17. Find the middle term of the AP 6, 13, 20, ..., 216.
​

Answer 1

Step-by-step explanation:

click the above image☝

this is the answer of your question

Answer 2

Answer:

Given,

a=6

d=13−6=7

T

n

=a+(n−1)d

216=6+(n−1)7

∴n=31

If n is odd then the middle term is

2

n+1

Middle term, =

2

31+1

=16

T

16

=6+(16−1)7=111.