Let `a_1, a_2, a_3, ....a_n,.........`be in A.P. If `a_3 + a_7 + a_11 + a_15 = 72,` then the sum of itsfirst 17 terms is equal to :

Let a_1, a_2 , a_3 and a_4 be in AP. If a_1 + a_4 =10 and a_2. a_3 =24 , then the least term of the AP, is

If a_1,a_2,a_3,. . . ,a_n. . . are in A.P. such that a_4−a_7+a_10=m , then sum of the first 13 terms of the A.P.is

For the A.P., a_1, a_2,a_3, ............., if a_4/a_7= 2/3 , find a_6/a_8 .

Let a_1,a_2,a_3 ......, a_n are in A.P. such that a_n = 100 , a_40-a_39=3/5 then 15^(th) term of A.P. from end is

If a_1, a_2, a_3 ,........ are in A.P. such that a_1 + a_5 + a_10 + a_15 + a_20 + a_24 = 225 , then a_1 + a_2+ a_3 + ......+ a_23 +a_24 is equal to

If a_1, a_2, a_3,.....a_n are in H.P. and a_1 a_2+a_2 a_3+a_3 a_4+.......a_(n-1) a_n=ka_1 a_n , then k is equal to

If a_1, a_2, a_3,.....a_n are in H.P. and a_1 a_2+a_2 a_3+a_3 a_4+.......a_(n-1) a_n=ka_1 a_n , then k is equal to

If a_1, a_2, a_3,.....a_n are in H.P. and a_1 a_2+a_2 a_3+a_3 a_4+.......a_(n-1) a_n=ka_1 a_n , then k is equal to