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प्रश्न
In the formula `barx = a + h((sumf_iu_i)/(sumf_i))`, for finding the mean of grouped frequency distribution, ui = ______.
पर्याय
`(x_i + a)/h`
`h(x_i - a)`
`(x_i - a)/h`
`(a - x_i)/h`
उत्तर
In the formula `barx = a + h((sumf_iu_i)/(sumf_i))`, for finding the mean of grouped frequency distribution, ui = `underlinebb((x_i - a)/h)`.
Explanation:
According to the question,
`barx = a + h((sumf_iu_i)/(sumf_i))`
Above formula is a step deviation formula.
In the above formula,
xi is data values,
a is assumed mean,
h is class size,
When class size is same we simplify the calculations of the mean by computing the coded mean of u1, u2, u3 …..,
Where ui = `(x_i - a)/h`
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