A man walks to a viewpoint and returns to the starting point by his car, taking a total time of 3 hours 30 minutes. He would have saved 3 hours by driving both ways. How long would it have taken for him to walk both ways with the same walking speed?

Ramesh covers 56 part of the total distance by bus and the remaining 36 km by car. What is the total distance of his journey?

A person covers a distance of L km in 12 hours. If he increases his speed by 10 m/s, he covers the same distance in 8 hours. Which of the following statements is/are correct? I. The value of L is 760 km. II. The original speed of the person is 72 km/h.