Question

find the 21 st term from the end of the A.P
LP is 4, 7, 10....304​

Answer 1

Answer:

A.P = 4,7,10...304

REVERSING THE A.P WE GET

A.P = 304,301,298...4

where a = 304 d = -3 and nTh term = 21

$a_{n} = a + (n-1)d\\a_{21} =304+(21-1)-3\\a_{21} = 304+(-60)=254$

Therefore the 21st term from the last of the A.P is 254