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# Following is the distribution of marks of 70 students in a periodical test: Marks Number of students Marks less than 10 Marks less than 20 Marks less than 30 Marks less than 40 Marks less than 50 3 11 28 48 70 Draw a cumulative frequency curve for the above data and find the median.

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## $\mathrm{We}\mathrm{plot}\mathrm{the}\mathrm{points}\mathrm{A}\left(10,3\right),\mathrm{B\left(20,11\right),}\mathrm{C\left(30,28\right),}\mathrm{D\left(40,48\right)}\mathrm{and}\mathrm{E\left(50,70\right) .}\phantom{\rule{0ex}{0ex}}\mathrm{Join}\mathrm{AB,}\mathrm{BC,}\mathrm{CD,}\mathrm{DE}\mathrm{and}\mathrm{EA}\mathrm{with}\mathrm{a}\mathrm{free}\mathrm{hand}\mathrm{to}\mathrm{get}\mathrm{the}\mathrm{curve}\mathrm{representing}\mathrm{the}\text{'}\mathrm{less}\mathrm{than}\mathrm{type}\text{'}\mathrm{series}.\phantom{\rule{0ex}{0ex}}$ ​$\mathrm{From}\mathrm{P\left(0,35\right)},\mathrm{draw}\mathrm{PQ \parallel x}-\mathrm{axis}\mathrm{meeting}\mathrm{the}\mathrm{curve}\mathrm{at}\mathrm{Q.}\phantom{\rule{0ex}{0ex}}\mathrm{Draw}\mathrm{QM\perp OX}\mathrm{meeting}\mathrm{the}\mathrm{x-axis}\mathrm{a}\mathrm{t}\mathrm{M.}\phantom{\rule{0ex}{0ex}}\mathrm{C}\mathrm{learly},\mathrm{OM= 33.5}\mathrm{u}\mathrm{nits.}\phantom{\rule{0ex}{0ex}}\mathrm{Hence},Median=33.5$  Suggest Corrections  0      Similar questions  Related Videos   Median
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