Question

if third
Term of Ap is 18 and 7th term is 30
find the Ap.​

Answer 1

$a_3=18\\\\a+2d=18----(i)\\\\also,\\\\a_7=30\\\\a+6d=30----(ii)$

$Subtracting$ $(ii)$ $equation$ $from$ $(i)$ $;$

$a+2d=18\\a+6d=30\\-------\\-4d=-12\\\\d=12/4\\\\d=3$

Putting value of d in (i) equation :

$a + 2(3) =18\\\\a = 18 - 6\\\\a = 12$

First term = a = 12

Second term = a + d = 15

Third term = a + 2d = 18

Fourth term = a + 3d = 21

$AP:12,15,18,21,......$

Answer 2

Answer:

Ap =12,15,18,21..........

Step-by-step explanation:

go through the picture for step by step guide