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Question
Coefficient of variation of two distributions are 50 and 60, and their arithmetic means are 30 and 25 respectively. Difference of their standard deviation is ______.
Options
0
1
1.5
2.5
Solution
Coefficient of variation of two distributions are 50 and 60, and their arithmetic means are 30 and 25 respectively. Difference of their standard deviation is 0.
Explanation:
Here, we have CV1 = 50, CV2 = 60
`barx_1 = 30` and `barx_2 = 25`
∴ CV1 = `sigma_1/barx_1 xx 100`
⇒ 50 = `sigma_1/30 xx 100`
⇒ `sigma_1 = (50 xx 30)/100` = 15
And CV2 = `sigma_2/barx_2 xx 100`
⇒ 60 = ` sigma_2/25 xx 100`
⇒ `sigma_2 = (60 xx 25)/100` = 15
∴ Difference `sigma_1 - sigma_2`
= 15 – 15
= 0
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