9. Sudhir walked \( \frac{7}{20} \mathrm{~km} \) more than Prem. Prem walked \( \frac{5}{8} \mathrm{~km} \) less than Rohan. Sudhir walked \( \frac{3}{5} \mathrm{~km} \). How much did Rohan walk?
10. I have to cycle a certain distance in the course of a day. I ride \( \frac{1}{8} \) of the whole journey before breakfast, \( \frac{2}{5} \) between breakfast and lunch, \( \frac{3}{10} \) between lunch and tea. What fraction of the journey remains? If the whole distance is 80 km , how much do I ride in each interval?
