Question

The ap of 5,10,15....is more than 31th in 58th term find the number of term

Answer 1

The given A.P. is 5,10, 15.......

Here,a=5 and d=10-5=5

an=a+(n-1)d

=)a13=5+(13-1)5

=)a13=5+12×5

=)a13=65

Let nth term be 13th term than the 58th term of the given A.P.

=)an-a13=58

=)an-65=58

=an=58+65

=)an=123

so,

5+(n-1)5=123

=)3+5n-5=123

=)5n-2=123

=)5n=123+2

=)5n=125

=)n=125/5

=)n=25

Hope it helps!