PostsInterview Question: Which Exit To Choose
Posted 01/06/2014

The Problem

Here's an interesting interview question I thought of on my way home from a party recently.

  1. You are parked at some starting point SP which is between 2 exits E1 and E2
  2. We were at a cross road with Road 1 R1 at our SP
  3. Our starting point is set between exit 1 and exit 2 on the highway E1 and E2 of road 2 R2
  4. To reach our destination we must reach exit 4 E4 which is past E2
  5. Speed limit of R1 = 25, R2 = 50 (double)

??? When will going to E1 be faster ???

From SP at which distance is it faster to go back to E1 instead of going forward to E2.

The Solution

In Conclusion

Its about how the interviewee answers the question, not the answer they give.
So, take note of the interviewees thought process while solving the problem.

Remember: The question is better when you word it like I did.
Do not say Which route is faster.
That is not the question, it is When is going backward faster.
This will force the interviewee to use a logical thought instead of a geometrical.