2019^th term of an AP is written as

If the nth term of an AP is (2n+1) then the sum of its first three terms is

. How many terms of the A.P. 65, 60, 55, … be taken so that their sum is zero?

Determine the AP whose fifth term is 19 and the difference of the eighth term from the thirteenth term is 20.

two APs have the same common difference. The first term of one of these is -1 and that of the other is – 8. Then the difference between their 4th terms is

If 7 times the 7th term of an AP is equal to 11 times its 11th term, then its 18th term will be

In an AP, if d = -4, n = 7, an = 4, then a is equal to

,

The next term of an AP  $\sqrt{7}$  , $\sqrt{28}$  , $\sqrt{63}$  ,......is 

The sum of first 'n' terms of an AP is (3n²+6n). The common difference of the AP is ______

The common difference of the AP  $\frac{1}{p}$ , $\frac{1-p}{p}$  , $\frac{1-2p}{p}$  ........is

The sum of first 20 odd natural numbers is

If 4, x₁,x₂,x₃,28 are in AP then x₃ is ______

The following are Arithmetic Progressions, except