A hungry spider is sitting on the floor in the corner of a rectangular room.

She sees a tasty fly on the ceiling in the far corner.   The room is a meters long, b meters wide, and c meters high.

What is the shortest route from the spider to the fly if the spider must always crawl along a wall?
Show your work!



Solution to the Problem:



The answer could also have been sqrt(a^2 + (b + c)^2) or sqrt(b^2 + (a + c)^2) since we don't know the relationship between a, b, and c.

The easiest way to see this is to "unfold" the sides of the room and draw a line segment between the spider and the fly.   Below is a diagram of the front face and the end face when it is unfolded.   The dashed line shows the path of the spider.



Now use the Pythagorean Theorem to solve for the distance.
(distance)2 = (a + b)2 + c2
Then take the square root of each side to obtain the answer.


Correctly solved by:

1. Kelly Stubblefield Mobile, Alabama
2. Ivy Joseph Pune, Maharashtra, India
3. James Alarie Flint, Michigan
4. Leah Snyder *** Nashville, Tennessee
5. Mia Tucker Mountain View High School,
Mountain View, Wyoming
6. Haylee Rudy Mountain View High School,
Mountain View, Wyoming
7. Soonho You (유순호) JeonJu, South Korea
8. Tyler Petersen Mountain View High School,
Mountain View, Wyoming
9. Haily Stephens Mountain View High School,
Mountain View, Wyoming
10. Drew Harris Delta High School,
Delta, Colorado
11. Brijesh Dave Mumbai City, Maharashtra, India

*** extra credit for sending multiple solutions for the problem.