The following frequency distribution gives the monthly consumption of electricity of 68 consumers of a locality. Find the median, mean and mode of the data and compare them. Monthly consump- 65-85 85-105 105-125 125-145 145-165 165-185 185-205 No. of consumers: 4 5 13 20 14 8 4

Explanation

We know that the Mean, (x) = a + (Σfᵢuᵢ/Σfᵢ) × h

Mode = l + [(f₁ - f₀) / (2f₁ - f₀ - f₂)] × h

and Median = l + [(n/2 - cf)/f] × h


So,let h=`20` and a=`135`

From the table, Σfᵢ =` 68` and Σfᵢuᵢ = `7`

Mean (x) = a + (Σfᵢuᵢ/Σfᵢ) × h


= `135 + (7/68) × 20`

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