[" (10) In an A.P."1^(" st ")" term is 1and the last term is 20.The sum of all terms is = 399"],[" then "n=....]

In an A.P., 1^(st) terms is 1 and the last term is 20. The sum of all terms is 399 then n = …………. A)42 B)38 C)21 D)19

In an A.P. I term is 0 and the last term is 40 . Then sum of all terms is =………. when n=20 .

In an A.P, 1st term is 1 and the last term is 20 .The sum of all terms is 399 , then n=…. a) 42 b) 38 c) 21 d) 19

In an A.P., the first term is 3 and the last term is 17. The sum of all the terms in the sequence is 70. Then the number of terms in the arithmetic sequence is

For an A.P., the first term is 5 and the last is 30. The sum of all the terms is 420. What is the value of n ?

In an A.P., first term is -5 and last term is 45. If sum of all the numbers in the A.P. is 120, then how many terms are there? What is the common difference.

In an A.P, first term is -5 and last term is 45 . If sum of all the numbers in the A.P is 120 , then how many terms are there? What is the common difference?

In an A.P, the first term is 1 and sum of the first p terms is 0, then sum of the first (p + q) terms is

In an A.P., the first term is 2, the last term is 29 and sum of the terms is 155. Find the common difference of the A.P.