Question

find the middle term of AP 6, 13, 20 upto 216

Answer 1

tn = 216
a=6
d= (13-6) = 7
Tn = 216
a +d(n-1) =216
6+7 (n-1)= 216
7(n-1) = 216 - 6
(n-1). = 210/7
n-1 =. 30
n = 31

Median =
$\frac{1}{2} (31 + 1)$
$16$
Tn = a +d(n-1)

${16}^{t}$
term 16 = a + d(n-1)
= 6 + 7×15
= 6+ 105
= 111