Question

a=4,S=144,and n=9 find its last term​

Answer 1

Step-by-step explanation:

Given, l = 28.

s = 144 .

n = 9 .

∴ Sum of n terms, s = 144

⇒

2

n

(a+l)=144.

⇒

2

9

(a+28)=144

⇒a+28=144×

9

2

⇒a=32−28

⇒a=4