Two A.P.'s have same common difference. If the difference between their 25^th terms is 8, the difference between their 50^th terms is :

1. 16

2. 5

3. 8

4. 25

Ten times the 10^th term of an A.P. is equal to twenty times the 20^th term of the same A.P. The 30^th term of this A.P. is :

1. 0

2. 40

3. 20

4. 2 × (30 + 10)

The 40^th term of an A.P. exceeds its 16^th term by 72. Then its common difference is :

1. 40

2. 40 - 16

3. 72

4. 3

The n^th term of the A.P. 6, 11, 16, 21, ……. is 106, the the value of n - 4 is :

1. 17

2. 15

3. 16

4. 20