How many terms are there in the A.P. 20, 25, 30, …100.

How many terms are there in the A.P. 7,10,13,…43?

How many terms are there in the A.P. 3, 7, 11, ... 407?

How many terms are there in the A.P. -1,\ -5/6,\ -2/3,-1/2,\ ,(10)/3?

How many terms are there in the A.P. whose first and fifth terms are -14 and 2 respectively and the sum of the terms is 40?

How many terms are there in the A.P. whose first and fifth terms are -14 and 2 respectively and the sum of the terms is 40?

The first and the last terms of an A.P. are 4 and 81 respectively . If the common difference is 7, how many terms are there in the A.P. and what is their sum?

How many terms of the A.P. 20, 19 1/3, 18 2/3, ……… must be taken so that their sum is 300?

How many terms of the A.P. : 24, 21, 18,…………... must be taken so that their sum is 78 ?

How many terms of the A.P. 24,20, 16, ... must be taken so that the sum may be 72? Explain the double answer.

How many terms of the A.P. 54, 51, 48, ... has the sum 513 ? Explain the double answer.