It reduces to 5/13
39/100 can't be reduced.
The fraction 39/200 cannot be reduced any more.
No.
13/39 = 1/3
Yes.
15.78 in fractions can be described as 15 and 78 one hundredths. This would be notated as 15 and 78 over 100. Seventy eight one hundredths can be reduced as 39 over 50, so the fraction would be notated as 15 39/50.
39/100 is as far as it goes
3/10
11 / 13
It is: 13/14
2/3