781. Three factories A, B, C have 100, 200 and 300 workers respectively. The mean of the wages is the same in the three factories. Which of the following statements is true?
A.There is greater variation in factory C.
B.Standard deviation in. factory A is the smallest.
C.Standard deviation in all the three factories are equal
D.None of the above

782. Which of the following measures of dispersion is independent of the units employed?
A.Coefficient of variation
B.Quartile deviation
C.Standard deviation
D.Range

783. The first and second moments about arbitrary constant are -2 and 13 respectively, The standard deviation will be:
A.-2
B.3
C.9
D.13

784. If the third central is negative, the distribution will be:
A.Symmetrical
B.Positively skewed
C.Negatively skewed
D.Normal

785. The lack of uniformity or symmetry is called:
A.Skewness
B.Dispersion
C.Kurtosis
D.Standard deviation

786. If mean=10, median=8 and standard deviation=6, then coefficient of skewness is:
A.1
B.-1
C.2/6
D.2

787. In a symmetrical distribution Q1 = 20 and median= 30. The value of Q3 is:
A.50
B.35
C.40
D.25

788. If there are ten values each equal to 10, then standard deviation of these values is:
A.100
B.20
C.10
D.0

789. If all values are considered equal in calculating an index, the index is
A. simple
B. weighted
C. un-weighted
D. None of these

790. Which price indices is made by Federal Bureau of statistics?
A. Consumer price index
B. Sensitive price index
C. The whole seller price index
D. All of the above