Coefficient of Variation

Q. If the mean of a data set is 25 and its coefficient of variation is 20, then find the standard deviation.

1. 5
2. 10
3. 15
4. 20

Q. If the mean of a data set is 25 and its coefficient of variation is 20, then find the standard deviation.

1. 5
2. 10
3. 15
4. 20

Q. Coefficient of variation can be defined as C.V = ___________.

1. = $\frac{standarddeviation}{mean}\times 100$
2. = $\frac{standarddeviation}{mean}\times 10$
3. = $\frac{mean}{standarddeviation}\times 100$
4. = $\frac{mean}{standarddeviation}\times 10$
   

Q. Coefficient of variation can be defined as C.V = ___________.

1. = $\frac{standarddeviation}{mean}\times 100$
2. = $\frac{standarddeviation}{mean}\times 10$
3. = $\frac{mean}{standarddeviation}\times 100$
4. = $\frac{mean}{standarddeviation}\times 10$
   

Q.

The coefficient of variation of two distributions are $50\%$ and $60\%$, and their arithmetic means are $30$ and $25$, respectively. The difference in their standard deviation is

1. $1$

2. $1.5$

3. $2.5$

4. $0$

Q. In a series of observations, S.D.$=7$ and mean is $28$, the coefficient of variation is

1. $4$
2. $1/4$
3. $25$
4. $12.5$

Q. The sum of the squares deviations for $10$ observations taken from their mean $50$ is $250$. The coefficient of variation is

1. none of these
2. $10$%
3. $40$%
4. $50$%

Q. Calculate arithmetic mean using direct method for the following data shows distance covered by $50$ persons to perform their work inside the factory.

1. $20.5km$
2. $32.8km$
3. $27.6km$
4. $25.2km$

Q. The cost of $2$ kg of Apples and $1$ kg grapes on a day was bound to be Rs. $160$. After a moth the lost of $4$ kg grapes and $2$ kg graps is Rs. $300$. Represent this situation algebraicallyand geometrically.

Q. Standard Deviation of a set of data is more than its mean. Find the percentage coefficient of variance.

1. less than 100
2. more than 100
3. equal to 100
4. None of the above

Q. If standard deviation of variate $x_i$ is 10, then variance of the variate $(50+5x)$ will be

1. 50
2. 250
3. 500
4. 2500

Q. Consider the following distribution of daily wages of 150 workers of a factory. Find the
mean daily wages by step deviation method.
Daily Wages (in Rs ) 20−30 30 −40 40 −50 50 −60 60 −70
Number of workers 25 40 42 33 10

Q. Standard deviation for n observations $x_1,x_2,\dots x_n$ is 5, then the standard deviation for n observations $x_1+1,x_2+1,\dots x_{n+1}$ will be ___

Q. The mean and standard deviation of a set of values are $5$ and $2$ respectively. If $5$ is added to each value, then what is the coefficient of variation for the new set of values?

1. $10$
2. $40$
3. $20$
4. $70$