It is 1/3 in its lowest terms
Yes.
16/39 is in its simplest form.
39/4
39/3 = 13/1 = 13
6/13
3/9 = 1/3
3/4
78 over 220 in the lowest terms is 39/110
9.78 in a mixed number is 9 78/100. In its lowest term, it is 9 39/50.
28/39
78/100 = 39/50
16:13 inches.