Interview Question

Senior User Experience Designer Interview

-Seattle, WA

Amazon

Question from director: "... four people need to cross a bridge at night, there is only one flash light and only one person can walk on the bridge at a time. How do would you get them all across the bridge?"

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Interview Answers

9 Answers

25

If a UX director asks this question, he wants to see how much of real UX designer you are, and how methodical you approach this task. A good UX designer needs to understand the real problem first. Based on the information given we can only make broad assumptions. A hypothesis based on limited data is a good starting point, but before we jump to premature "solutions", the first task is to do more digging. We need to ask questions (and do research) to understand the actual problem before we can propose a a fitting solution - a user experience that truly solves the unique problem these four people have in their specific situation (it might even turn out that they don't need to cross a bridge at night but need something completely else, but let's not go that far here). So - based on the information given, we don't know what type of bridge it is (does it have a railing, is the bridge lit, short, long, is there even pavement or gravel and potholes, is there traffic, etc...), we need to understand WHY only one person can walk on the bridge and whether the people even need to walk (they might be able to drive, maybe there is a bus that can transport them). Where is the flash light, what type of flash light is it And who are these individuals? What is the relationship between these people? Do they all have the same motivation to cross the bridge? WHY do they need to cross the bridge? Is that really what they need, or do they have a different problem? Also, are they all on the same side? Why do they need to cross the bridge at night, do they have to cross the bridge every night or just once? Etc. etc. -You get the point. In addition: What are my resources to get them over the bridge? Which technical and business opportunities and constraints do I have? In which time duration do I have to get them cross the bridge? Fun exercise for a UX candidate.

Anonymous on

14

Nope, only 1 person at a time, remember? just have the last person shine the flashlight on the bridge while the other people cross and then cross last.

Anonymous on

2

Well, why do you need a flashlight to cross a bridge? A blind person can cross a bridge, no? Can you not keep a hand on the railing and feel your way across? Can you not feel the rumble of traffic passing and keep away? Sure, it feels safer with a light, so let's go with that. You need to see what's ahead, so the first three people take turns shining the light from behind as one person crosses at a time. Then the fourth person crosses with the flashlight.

Anonymous on

4

This is a UX question; each person must experience the Journey with the flashlight. In a situation that there isn't a string, each person takes the flashlight up and down the bridge, while marking or taking metal note of the path they take, while going back. The person will then return the flash light to another while walking back without the flashlight. Once the person gets back to the others, he/she drop the flashlight and cross the bridge following the pattern or marking that he or she created. The pattern and design will be followed by everyone. Leaving the flashlight for another person to use. It is about creating a design that others can use and be successful at.

Interview Answer on

1

If they are crossing the bridge in the daytime they don't need a flasjlight.

Anonymous on

2

Solution 1: Question said cross the bridge and did not say need to stay on the other side of the bridge. Person 1 to 3 cross with flashlight. Then any one of them return with flash light for the 4th to cross with flash light. One person would remain but all would have crossed. Solution 2: Whoever got to the other side go buy 3 more torch lights so all 4 can cross with minimal back and forth. Solution 3: Tie a really long string to the flash light. After first person uses it to get across, second person pulls it back by the string. Repeat the process.

Aen on

0

The first person walks across, turns around, and shines the light back at the rest of the group. Then the group has a light to walk toward.

Anonymous on

0

Tie a string to the flashlight so the people on the first side can pull the flashlight back to their side of the bridge.

Anonymous on

2

The first person carries the second person across on his back. The second person goes back to retrieve the third person and carries him across. The third person goes back for the fourth person and carries him across.

Anonymous on

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