Question

Which term of the AP : 21,42,63,84.....is 210

Answer 1

Answer:

n=10

Step-by-step explanation:

GIVEN:-a=21,d=21,aₙ=210

TO FIND:- nth term.

Formula Used:- aₙ=a+(n-1)d

Solution:-

=>aₙ=a+(n-1)d

=>210=21+(n-1)(21)

=>210-21=21n-21

=>189+21=21n

=>210=21n

=>n=$\frac{210}{21}$

=>n=10