Question

14. Determine the ap whose 3rd term is 5 and the 7th term is 9.

Answer 1

Hii !!



3rd term = 5


a + 2d = 5


a = 5 - 2d -----(1)



And,



7th term = 9


a + 6d = 9 -------(2)


Putting the value of a in equation (2) , we get








a + 6d = 9


5 - 2d + 6d = 9




4d = 4


d = 1.



Putting the value of d in equation (1) , we get


a = 5 - 2d = 5 - 2 × 1

a = 3


First term ( a ) = 3

And,

Common difference ( d ) = 1.





Therefore,

AP = 3 , 4 , 5 , 6 , 7 .........