Question

without using the formula for the nth term, find which term of the AP:5,17,29,41,..will be120 more than its 15th term?

Answer 1

as it is an AP the difference between any consecutive term is same
here the difference  = 17-5 =12
so the difference between 15th and 16th term will be 12 
15th and 17th term will be 24 and so on hence the difference between 15th and 25th term will be 12*(25-15) = 120

Answer 2

this is the answer i solved it for u
hope it helps