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The marks obtained by 120 students in a mathematics test is given below:

    \[\begin{tabular}{|l|l|} \hline Marks & No. of students \\ \hline $0-10$ & 5 \\ \hline $10-20$ & 9 \\ \hline 20-30 & 16 \\ \hline 30-40 & 22 \\ \hline 40-50 & 26 \\ \hline 50-60 & 18 \\ \hline 60-70 & 11 \\ \hline 70-80 & 6 \\ \hline 80-90 & 4 \\ \hline $90-100$ & 3 \\ \hline \end{tabular}\]

Draw an ogive for the given distribution on a graph sheet. Use a suitable scale for your ogive. Use your ogive to estimate:
(i) the median
(ii) the number of students who obtained more than in test.
contexto.140

Solution:

(i) Median term

Draw a parallel line to through mark which meets the curve at A. From A draw a perpendicular to meeting it at B.

Therefore, the value of point B is the median

(ii) No. of students who obtained up to 75% marks in the test

No. of students who obtained more than 75% marks in the test