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प्रश्न
A group of 65 students of class XI have their average height is 150.4 cm with coefficient of variation 2.5%. What is the standard deviation of their height?
उत्तर
Given, n = 65, `bar"x"` = 150.4, C.V. = 2.5%
C.V. = `(sigma)/bar"x" xx 100`
∴ 2.5 = `(sigma)/(150.4) xx 100`
∴ `(2.5 xx 150.4)/(100) = sigma`
∴ `sigma = (376)/(100)`
∴ `sigma` = 3.76
∴ The standard deviation of students height is 3.76.
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