Question

what is the 17th term from the end of the AP 11,16.......211,216

Answer 1

To find the 17th term from the end,we use

An = l - (n - 1) d
where

l = last term
n = number of term
d = difference between two consecutive terms

A17 = 216 - (17 - 1)(5)
A17 = 216 - (16 × (5))
A17 = 216 - 80
A17 = 136

The 17th term from the end = 136

Answer 2

Yea fine... My dear friend, Here is Yr answer..

$a = 11 \\ d = 16 - 11 = 5 \\ \: \: \: \: = 216 - 211 = 5 \\ so \: \: \: \: \: d = 5 \\ \\ n \: is \: given \: as \: 17. \\ so \: \: n = 17. \\ \\ so \: by \: formula \\ a{n} \: = \: a + (n - 1)d \\ \: \: \: \: \: \: \: = 11 + (17 - 1)5 = 80 + 11 = 91. \\ \\ so \: required \: answer \: is \: 91.$