Question

Which term of the AP 21 18 15 is -81

Answer 1

Answer:

An=-81, a=21, d= -3

an=a+(n-1) d

-81=21+(n-1)(-3)

-102=(n-1)(-3)

34=n-1

n= 35

There for the 35 the term is -81

Hope it helps you...

Answer 2

plz refer to this attachment