Embibe Experts Solutions for Chapter: Statistics, Exercise 4: Exercise-4

If standard deviation of $1, 2, 3, 4, 5$ is $\sqrt{2}$, then which of the following is correct.

In a batch of $20$ students, $8$ have failed. The marks of the successful candidates are $23, 27, 29, 18, 17, 19,21, 27, 20, 24, 26, 28$ the median marks are

The coefficient of variation of two series are $60\%$ and $70\%$, if their standard deviation are $21$ and $14,$ then find ratio of their AMs

The mean of $2$ samples of sizes $50 \& 40$ were found to be $63$ and $54 .$ Their variance were $81 \& 36.$ Find the variance of combined sample of size $90$

The mean and median of some data is $14$ and $12$. Later it was discovered that every data element should be increased by $2$ units, then new mean and median will be

Rohan worked for a firm as given below:

What is the mean number of days Rohan works per week?

If a variate $X$ is expressed as a linear function of two variates $U$ and $V$ in the form $X=aU+bV,$ then Mean $\overline{X}$ of $X$ is

The AM of $n$ numbers of a series is $\overline{X}.$ If the sum of first $\left(n-1\right)$ terms is $k,$ then the $n$th number is