Question

Which term of an AP ,4,9,14,....is 254?

Answer 1

4+(n-1)5=254
4+5n-5=254
5n=255
n=51

Answer 2

Hey,

Here the first term = a = 4 
and 
the common difference = d = 9 - 4 = 5

Let n th term of the given A.P. be 254, then,

a+(n-1)d=254

4+(n-1)5=254

5n=255

n=51

Hence, the 51 th term of the given A.P. is 254.

HOPE IT HELPS YOU:-))