Find the mean deviation from the mean of the following data: Classes:, 10-20, 20-30, 30-40, 40-50, 50-60, 60-70, 70-80 frequency, 2, 3, 8, 14, 8, 3, 2

Explanation

Given,


`[[cf],[10-20],[20-30],[30-40],[40-50],[50-60],[60-70],[70-80],[total]]`
`[[f_i],[2],[3],[8],[14],[8],[3],[2],[40]]`
`[[x_i],[15],[25],[35],[45],[55],[65],[75],[315]]`
`[[f_ix_i],[30],[75],[280],[630],[440],[195],[150],[1800]]`
`[[(|x_i--barx|)],[30],[20],[10],[0],[10],[20],[30],[120]]`
`[[(f_i(|x_i--barx|))],[60],[60],[80],[0],[80],[60],[60],[400]]`

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