Solution:
(i)We arrange given marks in ascending order
7, 10, 12, 12, 14, 15, 16, 16, 16, 17, 19
16 appears maximum number of times.
Hence his modal mark is 16.
(ii)Here number of observations, n = 11 which is odd.
So Median = ((n+1)/2)th term
= (11+1)/2
= 12/2
= 6th term
= 15
Hence the median is 15.
(iii) Mean = Ʃxi/n
= 7+ 10+12+12+14+ 15+16+16+16+ 17+ 19
= 154/11
= 14
Hence the mean is 14.