How many terms are there in the AP 20, 25, 30...,130
Find the 1st term of an AP whose 8th & 12th terms are respectively 39 & 59.
There is an AP 1,3,5....Which term of this AP is 55?
How many terms are identicle in the two APs 1,3,5,... up to 120 terms & 3,6,9,... up to 80 terms ?
Find the 15th term of the sequence 20,15,10...