Travellers Riddle

Riddle: Two travelers spend from 12 o'clock to 6 o'clock walking along a level road, up a hill, and back again. Their pace is 4 mph on the level, 3 mph uphill, and 6 mph downhill. How far do they walk and at what time do they reach the top of the hill?

Answer: 24 miles half past three. Source: https://riddles.com/3276

Two travelers spend from 12 o'clock to 6 o'clock walking along a level road, up a hill, and back again. Their pace is 4 mph on the level, 3 mph uphill, and 6 mph downhill.
How far do they walk and at what time do they reach the top of the hill? — Travellers Riddle by don orr Riddle