Question

The 10th term of the AP 21,18,15 is

Answer 1

Answer:

ThegivenA.Pis21,18,15.....

so,

a=21

a+d=18

∴d=−3

now

a(nthterm)=a+(n−1)d

⇒0=a+(n−1)d

⇒0=21+(n−1)(−3)

⇒n−1=

−3

−21

⇒n−1=7

⇒n=7+1

∴n=8

Hence,therequiredtermis8.