Coefficients of variation of two distributions are 50 and 60, and their arithmetic means are 30 and 25, respectively. Difference of their standard deviations is
a. 0
b. 1
c. 1.5
d. 2.5

Answer

A

Explanation

Here, `(CV)_(1)=50,(CV)_(2)=60,overline(x_(1))=30 " and" overline(x_(2))=25`
` therefore (CV)_(1)=(sigma_(1))/(overline(x_(1)))xx100`
`implies 50=(sigma_(1))/(30)xx100`
`therefore sigma_(1)=(30xx50)/(100)=15`
and `CV_(2)=(sigma_(2))/(overline(x_(2)))xx100`
`implies 60=(sigma_(2))/(25)xx100`
`therefore sigma_(2)=(60xx25)/(100)=15`
Now, `sigma_(1)-sigma_(2)=15-15=0`