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Puzzle #167: Can you work out the fastest method of travel to take?

By Brian Hobbs

11 May 2022

#167 This escalated quickly

At the shopping mall, while their mother’s attention is conveniently fixed on a window display, Jill furtively approaches her brother.

“Hey, what do you say to a race up to the next floor and back? Winner does the other one’s chores.”

“You’re on,” says Jack.

There are two escalators that move at the same speed, one going up and one going down, and also a regular set of stairs.

The children decide that each will choose on which of the three they want to race, but whatever they pick, they will have to run both up…

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