From a sack of potatoes weighing 120 kg, a merchant sells lots weighing 6 kg, \(5 \frac{1}{4}\) kg, \(9\frac{1}{2}\) kg, and \(9 \frac{3}{4}\) kg respectively. How much potato is still left unsold?
1
\(89 \frac{1}{2} \ kg\)
2
\(20 \frac{1}{2} \ kg\)
3
358/2 kg
4
\(10 \frac{1}{2} \ kg\)