18^th term of an A.P. is equal to 4 times its 4^th term and the 6^th term exceeds twice the 2^nd term by 4. Find the sum of the first 9 terms of this A.P.

If A, B and C are three arithmetic progressions (APs) as given below :

A = 2, 4, 6, 8, …….. upto n terms

B = 3, 6, 9, 12, …… upto n terms

C = 0, 4, 8, 12, …… upto n terms, then

out of A + B, A - C, C - B and B - A which is/are A.P. ?

1. A + B

2. A - C

3. C - B

4. All are A.P.

Do the numbers 1², 5², 7², 73 ….. form an A.P. ? If yes, its next term will be :

1. Yes, 11²

2. No

3. Yes, 97

4. Yes, 24

The sum of first 10 even natural numbers is :

1. 120

2. 110

3. 65

4. 120