Embibe Experts Solutions for Chapter: Statistics, Exercise 1: Exercise 1

If the mean of five observations $x,x+2,x+4,x+6$ and $x+8$ is $11$, then the mean of last three observations is

The mean of first three terms is $14$ and mean of next two terms is $18$. The mean of all the five terms is

The mean square deviation about $-1$ and $+1$ of a set of observations are $7$ and $3$ respectively then standard deviation of the set is :-

A group of $10$ observations has mean $5$ and standard deviation as $2\sqrt{6}$. another group of $20$ observations has mean $5$ and standard deviation as $3\sqrt{2}$, then the standard deviation of combined group of $30$ observations is :-

The mean deviation from mean of observations $5,10,15,20,\dots \dots \dots 85$ is:-

The variance of $2,4,6,8,10$ is:

The variance of observations $112,116,120,125,132$ is:

Variance of the group $\alpha ,\alpha +2,\alpha +4,\alpha +6$, upto $n$ terms $\left(\alpha \ne 0\right)$ is :-