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Question
The sum of 10 values is 100 and the sum of their squares is 1090. Find out the coefficient of variation.
Solution
∑X = 100
N = 10
So, `overlineX = (sumX)/N = 100/10 = 10`
`sumX^2 = 1090`
`sigma = sqrt((sumX^2)/N - (overlineX)^2)`
= `sqrt(1090/10 - (10)^2)`
= `sqrt9`
= 3
CV = `sigma/overlineX xx 100`
= `3/10 xx 100 = 30`
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