Question

Which term of the A.P 12,18,15,...... is. ? State with reason is there any term 0 in this A.P ?

Answer 1

Answer. tn=-81

a=21,d=-3

tn=a+(n-1)×d

-81=21+(n-1)×-3

-81=21+3n+3

24+3n=-81

3n=-81-24

3n=105

n=105÷3

n=35

Therefore 35th term is -81

Yes there is a 0 term in this AP

Reson. It's starts from + to - so it has 0 in the scale