- Find the sum of 20 terms of the A.P. 1,4,7,10………
- If the nth terms of an A.P is (2n + 1), find the sum of first n terms of the A.P.
- Find the sum of first 30 terms of an A.P.whose second term is 2 and seventh term is 22.
- Find the sum of first 10 terms of an A.P., in which 3rd term is 7 and 7th term is two more than thrice of its 3rd term.
- Find the sum of all even integers between 2 to 100 divisible by 2.
- Find the number of terms in the series 20, 19 1/3 + 18 2/3 +………of which the sum is 300,explain the double answer.
- If the mth term of an A.P. is 1/n and the nth terms is 1/m, show that the sum of mn terms is ½(nm + 1).
- If the sum of n terms of an A.P.is same as the sum of its n terms, show that the sum of its (m + n) terms is zero.
- Find the sum of first n odd natural numbers.
- If the 8th terms of an A.P.is 31 and the 15th terms is 16 more than the 11th terms find the sum of first 20 terms.
- How many terms of A.P.: 24,21,18,…….. Must be taken so that their sum is 78?
- The angles of a triangle are in AP.If the greatest angle equals the sum of the other two, find the angles.
- Find the sum of two digits numbers, which are divisible by 7?
- Find the sum of number b/t 49 to 500 which are divisible by 7?
- If the pth term of an A.P.is q and the qth term is p, prove that its nth term is (p + q – n) and find the sum of first (p+q)th term .
- How many terms of the sequence 18,16,14…… should be taken so that their sum is zero.
- Write the first 5 terms of an AP whose nth term is given by (2n+1)/3.
- How many terms in the sequence -6 , -11/2 , -5 , -9/2 , …are needed to give the sum 0 ?
- Find the sum of all the natural numbers less than 100 which are divisible by 6.
- The sum of n terms of an A.P.; be 3n2 – n and its common difference is 6,find its first and 27th term.
- The sum of nth terms of an A.P. is 3n2+ 5n, then find its nth term.
- Find the sum of first 21 terms Ö2 + Ö8 + Ö18 + Ö32………….
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