(a) The minimum number of times
The number which appeared the minimum number of times (i,e, 4 times) is 4
(b) The maximum number of times
The number which appeared the maximum number of times (i,e, 11 times) is 5
(c) Find those numbers that appear an equal number of times.
1 and 6 are the number which appears for the same number of times (i,e, 7 times)