Question

Which term of ap 21, 42,63, 84_ is 210​

Answer 1

Answer:

Here, a=21,d=42-21=21 and Tn =210

Now

Tn =a+(n-1) d

210= 21+(n-1) 21

210= 21+21n-21

210=21n

n= 210/21

n=10

Hence, there are total 10 terms in the given A.P.