The following data shows marks obtained by 40 students in a Statistics test.

75 99 72 54 25 40 65 32 69 10 85 48 52 80 

63 64 35 62 51 71 67 57 95 74 56 69 61 

49 45 63 39 73 53 82 76 50 66 60 55 62 

Construct a grouped frequency distribution with the intervals of 10 starting from

10-19, 20-29 etc

a) Find 

i) Mode     

ii) Median    

iii) Inter-quartile range   

iv)  Co-efficient of variation based on Quartile    

b) Comment on the

 i) Symmetry     

 ii) Peakedness of the distribution