Obtain arithmetic mean of 2 and 128

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.

Statement 1 If one root of Ax^(3)+Bx^(2)+Cx+D=0 A!=0 , is the arithmetic mean of the other two roots, then the relation 2B^(3)+k_(1)ABC+k_(2)A^(2)D=0 holds good and then (k_(2)-k_(1)) is a perfect square. Statement -2 If a,b,c are in AP then b is the arithmetic mean of a and c.

Coefficient of variation of two distributions are 50 and 60, and their arithmetic means are 30 and 25 respectively. Difference of their standard deviation is ……

12 is arithmetic mean between x and 22 then x = ............

Let A_(1),A_(2),A_(3),"......."A_(m) be arithmetic means between -3 and 828 and G_(1),G_(2),G_(3),"......."G_(n) be geometric means between 1 and 2187. Product of geometric means is 3^(35) and sum of arithmetic means is 14025. The value of n is

Let A_(1),A_(2),A_(3),"......."A_(m) be arithmetic means between -3 and 828 and G_(1),G_(2),G_(3),"......."G_(n) be geometric means between 1 and 2187. Product of geometric means is 3^(35) and sum of arithmetic means is 14025. The value of m is

Two consecutive numbers from 1,2,3 …., n are removed .The arithmetic mean of the remaining numbers is 105/4 The sum of all numbers

Two consecutive numbers from 1,2,3,"……n" are removed. The arithmetic mean of the remaining numbers is (105/4) . The value of n lies in

If the arithmetic mean of a_(1),a_(2),a_(3),"........"a_(n) is a and b_(1),b_(2),b_(3),"........"b_(n) have the arithmetic mean b and a_(i)+b_(i)=1 for i=1,2,3,"……."n, prove that sum_(i=1)^(n)(a_(i)-a)^(2)+sum_(i=1)^(n)a_(i)b_(i)=nab .

Two consecutive number p,p + 1 are removed from natural numbers. 1,2,3, 4……….., n-1, n such that arithmetic mean of these number reduces by 1, then (n-p) is equal to.