Question

$\large\mathbf{HEY\: QUESTION❤}$


The 7th term of an A.P. is 20 and its 13th term is 32. Find the A.P.


★ REQUIRED QUALITY ANSWER​

Answer 1

A7 = 20

A13 = 32

A7 = A + 6D

20 = A + 6D...(i)

A13 = A + 12D

32 = A + 12D...(ii)

Subtracting (i) from (ii)

32 = A + 12D

20 = A + 6D

- - -

12 = 6D

D = 2

20 = A + 6D (from (i))

20 = A + 36

A = -16

Answer 2

GIVEN :

7th term of the AP = 20

i.e : a + 6d = 20 ─────> eq (1)

13th term of the AP = 32

i.e : a + 12d = 32 ─────> eq (2)

subtracting eq (1) from eq (2)

a + 12d - 32 = a + 6d - 12

=> 6d = 12

=> d = 12/6

=> d = 2

Now we need to find a

so putting the value of d in eq (2)

a + 6d = 20

=> a + 6(2) = 20

=> a + 12 = 20

=> a = 20 - 12

=> a = 8

AP SEQUENCE : a, a + d, a + 2d, a + 3d

a = 8

d = 2

8 , 8 +2 , 8 + 2(2) , 8 + 3(2)

AP : 8 , 10 , 12 , 14

HOPE THIS WILL HELP YOU... ❤