If the mean deviation about median for the numbers 3, 5, 7, 2k, 12, 16, 21, 24, arranged in the ascending order, is 6 then the median is :
Solution
<p>Median $= {{2k + 12} \over 2} = k + 6$</p>
<p>Mean deviation $= \sum {{{|{x_i} - M|} \over n} = 6}$</p>
<p>$$ \Rightarrow {{(k + 3) + (k + 1) + (k - 1) + (6 - k) + (6 - k) + (10 - k) + (15 - k) + (18 - k)} \over 8}$$</p>
<p>$\therefore$ ${{58 - 2k} \over 8} = 6$</p>
<p>$k = 5$</p>
<p>Median $= {{2 \times 5 + 12} \over 2} = 11$</p>
About this question
Subject: Mathematics · Chapter: Statistics · Topic: Measures of Central Tendency
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