Arithmetic progression class 10 part 3

Arithmetic progression | class 10 | Exercise 5.1 |

Arithmetic progression class 10 || Basic introduction

The sum of the fourth and twelfth term of an arithmetic progression is 20. What is the sum of the first 15 terms of the arithmetic progression?

If the sum of the first 100 terms of an arithmetic progression is -1 and the sum of the even terms is 1, then the 100^("th") term of the arithmetic progression is

The first term of an arithmetic progression is 1 and the sum of the first nine terms equal to 369 . The first and the ninth term of a geometric progression coincide with the first and the ninth term of the arithmetic progression. Find the seventh term of the geometric progression.

The first term of an arithmetic progression is 1 and the sum of the first nine terms equal to 369 . The first and the ninth term of a geometric progression coincide with the first and the ninth term of the arithmetic progression. Find the seventh term of the geometric progression.

The sum of the first fifteen terms of an arithmetical progression is 105 and the sum of the next fifteen terms is 780. Find the first three terms of the arithmetical progression,.

If x, y, z are in arithmetic progression and a is the arithmetic mean of x and y and b is the arithmetic mean of y and z, then prove that y is the arithmetic mean of a and b.

(a) The nth term of a progression is (3n + 5) . Prove that this progression is an arithmetic progression. Also find its 6th term. (b) The nth term of a progression is (3 - 4n) . Prove that this progression is an arithmetic progression. Also find its common difference. (c) The nth term of a progression is (n^(2) - n + 1). Prove that it is not an A.P.

If the number of ways of selecting 3 numbers out of 1, 2, 3, ……., 2n+1 such that they are in arithmetic progression is 441, then the sum of the divisors of n is equal to