The graph above shows the cumulative frequency curve of the distribution of marks in a class test. What percentage of the students scored more than 20 marks...

The graph above shows the cumulative frequency curve of the distribution of marks in a class test. What percentage of the students scored more than 20 marks?

Answer Details

$\begin{array}{ccc}\text{class-marks(x)}& \text{(freq. (f)}& \text{cum. freq.}\\ 9& & \mathrm{3.....3}\\ 14& & \mathrm{6....3}+6=9\\ 19& & \mathrm{9.....9}+9=18\\ 24& & \mathrm{3.....18}+3=21\\ 29& & \mathrm{2.....21}+2=23\\ 34& & \mathrm{2.....23}+2=25\\ & & 25\end{array}$
% of students scoring more than 20 marks

= $\frac{7}{25}$ x 100% = 28%