Selecting from a list returned by Tuples

Question

Select[Tuples[{1, 1/2}, {4, 4}], Total [#] == 15]

I want to select all tuples in the result returned by Tuples that have total of their elements equal to 15. The answer I got was only {}. Why?

Answer 1

There was an excelent answer with an illustration, but I would like to point out the specific mistakes:

• Pure function in the second argmuent should end with &
• Total[#] by default only sums on the first level, but you need more.