Find the number of common terms in two A.P.'s 1, 4, 7, ... & 9, 16, 23, ..... that are less than 100.

Find the number of terms in the A.P. 7, 10, 13, .........., 31.

Find the number of terms common to the two AP's 3,7,11,15....407 and 2,9,16......09.

Find the sum of 50 terms of the A.P. 1 + 4 + 7 + ....

Find the sum of 20 terms of the A.P.1,4,7,10..

Find the sum of first 100 terms of A.P. 14, 16, 18,……..

Find the number of common terms in the following sequences : 1, 5, 9, ... to 100 terms and 4, 7, 10, ... to 100 terms.

Find the sum to 25 terms of the A.P. 5, 7, 9, 11, …

9.The number of common terms in two A.P's 2,7,12,17..........500terms and 1,8,15,22........300 terms.is

Find the common difference of the A.P. 10, 7, 4, ........... .

(i) Find the number of terms in the A.P. 8, 12, 16, ........124 (ii) Find the number of terms in the A.P. 75, 70, 65, .....15