Ram works 20 hours in a week (Monday to Friday). Last week he worked \(\frac{{13}}{2}\) hours on Monday, 3 hours on Tuesday, \(\frac{{15}}{4}\) hours on Wednesday, and \(\frac{5}{2}\) hours on Thursday. How many hours did he work on Friday?
1
\(\frac{{15}}{4}\)
2
\(\frac{{143}}{4}\)
3
\(\frac{{17}}{4}\)
4
\(\frac{{-17}}{4}\)