Question

The 4 term of an ap is 11. The sum of the 5 and 7 term is 34 find the common difference

Answer 1

Answer is d = 3 .....

Answer 2

Hey !!
We know that nth term of AP is given by
an = a+(n-1)d
Given :- a4 = 11
a5+a7 = 34

Thus :-- a4 = a+3d --------1
a5 = a+4d
a7 = a+6d

Now ATQ :- a5+a7 = 34 => a+4d+a+6d = 35
=> 2a+10d = 34
= a+5d = 17---------2
Now from equation 1
a = 11-3d
put it in equation 2

=> 11-3d+5d = 17
=>2d = 6
=> d = 3
Hence common difference will be 3