hi
here is the data of students in a class

1,3,6,7,8,9,10,11,19,19,20,24,26,28,30

my questions is using equal width bins to smooth the data, and number of bins are 3

what will be the bins using bin boundaries to smooth the data, according to me answer is 

bin1: 1,3,6,7,8,9,10
bin2: 11,19,19,20
bin3: 24,26,28,30

using bin boundaries

bin1: 1,1,10,10,10,10,10,10
bin2: 11,20,20,20
bin3: 24,24,30,30 (here is my doubt it should be 24 or 21 because we are taking boundary from 21 to divide the bin that is 1-10,11-20,21-30).

please reply me as soon as possible

one more question is
 
for bin mean to smooth data
 
when i take mean of say bin 1 its coming in decimals like 12.6 so what should i write 12.6 or 13 beacuase we are dealing with data which has number of students how can it be in decimals

please reply as soon as possible

thank you