Sam Loyd's Trolley Puzzle - Solution

The Puzzle:

Sam Loyd's Trolley Puzzle
Charley Smalleash treats his best girl to a trolley ride, but on account of his limited resources they plan to walk back, so, if the car goes at the rate of nine miles an hour and they can walk at the rate of three miles an hour, how far could they ride if they must be back in eight hours?

Our Solution:

Charley Smalleash and his best girl could trolley three times as fast as they could walk. Therefore, three-quarters of their outing time was spent in walking, and but one-quarter in riding, since they had to walk back.

They rode for two hours, going 18 miles, and walked back in six hours, thus consuming their eight hours.
Puzzle Author: Loyd, Sam

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