If a and l are first and last terms of an A.P. then the number of terms is ….

The first and last terms of an A.P. are 1 and 7 . If the sum of its terms is 36 , then the number of terms will be

The first and last terms of an A.P. are 1 and 7 . If the sum of its terms is 36 , then the number of terms will be

The first and last terms of an A.P. having a finite number of terms are respectively (-2) and 124 and the sum of the A.P. is 6161. Find the number of terms in the A.P. and also its common difference.

The first and last terms of an A.P. are 1 and 11. If the sum of its terms is 36, then the number of terms will be (a) 5 (b) 6 (c) 7 (d) 8

The first and last term of an A.P. are 1 and 11. If the sum of its terms is 36, then the number of terms will be

If ‘a’ is the first term, ‘d' the common difference and 'l' the last term of an A.P., then the sum of the series is : (l^2-a^2)/(2d)+1/2(a+l) .

An A.P., and a H.P. have the same first and last terms and the same odd number of terms. The middle terms of the three series are in

An A.P., and a H.P. have the same first and last terms and the same odd number of terms. The middle terms of the three series are in

The first and last terms of an A.P. are - 7 and 233 and the sum of the A.P. is 9153. Find the number of terms in the A.P.: