This was also another question which was reportedly attempted by majority of the candidates and their performance was described as fair. It was also reported that many candidates drew bar charts instead of histograms while others did not use class boundaries in drawing the graph but they rather used class limits. Interpretation of the graph was also an observed challenge.
The grouped frequency table is given by
Class f Cf Class
Interval Boundary
21-30 2 2 20.5 - 30.5
31-40 10 12 30.5 - 40.5
41-50 12 24 40.5 - 50.5
51-60 15 39 50.5 - 60.5
61-70 8 47 60.5 - 70.5
71-80 3 50 70.5 - 80.5
The graph is given below
The modal mark derived from the graph = 53 while the probability = no. of candidates who scored marks greater than 63 ÷ total number of students i.e. 9/50 = 0.18.
