Question

Which term of the series 7 10 13 16 19 ____ is 151?

Answer 1

So the first term of the A.P. is 7= a and Common Difference is 10-7 =3 =d. The nth term of an A.P. is a+(n-1)d => let the nth term of an A.P. is 151=> 151 =7+(n-1)3 => 151 =7+3n-3 =3n+4 => 151-4 =147 =3n => n=147/3 => n=49. So the 49th term of the series is 151.

Answer 2

hey mate!

a=7. d=10-7=3. , n=? , an=151

an=a+(n-1)d
151=7+(n-1)3
151-7=3n-3
144=3n-3
144-3=3n
141=3n
141/3=n
47=n

thus 47th term of the the above AP is 151...

hope it helps!!