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There's a spider lurking on the floor in the corner of a room.

A fly comes to rest on the diagonally opposite corner of the floor and falls asleep.

The spider sets out for the fly; but for his own safety, he does not walk on the floor.

If the room is 40' x 56' with an 8' ceiling, how far must the spider walk for his lunch?

What if the floor is only 4' x 6'?

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~85 feet (up the wall, diagonally across the ceiling, and back down. shorter than going around the room on the wall, which would be 96 feet)

If the floor is 4x6, then 10 feet (around the room on the wall) since going across the ceiling would be ~23 feet

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Can't the spider just walk along the wall, around the edge of the room, staying as close to the floor as possible. If this is true, then the spider would only walk 40+56 = 96 feet.

However, if the spider goes up and over, then using pythagorean's theorem, the diagonal of the room is approximately 68.82 feet. So add 16 for the trip up to the ceiling and back down. Meaning the spider walks ~84.82 feet, which is a bit shorter than the other way..

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Forgot to add - the spider has a range of only 82' then he dies of hunger. :o

Does he survive?

;)

In the smaller room easy, just walks around the walls. In the bigger room goes up and across the ceiling diagonal then lets go in the corner above the fly and gravity does the rest

;)
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Forgot to add - the spider has a range of only 82' then he dies of hunger. :o

Does he survive?

If the spider is particularly clever, he can make it in 79.2 feet by going diagonally up the wall at a 45-degree angle, crossing the ceiling at a 45-degree angle, and coming down the opposite wall at a 45-degree angle. If his range is only 82 feet, it's gonna be close.

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Forgot to add - the spider has a range of only 82' then he dies of hunger. :o

Does he survive?

Well, if the spider travels at almost the speed of light, then the fly... spider... um... -- ah, forget it.

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There's a spider lurking on the floor in the corner of a room.

A fly comes to rest on the diagonally opposite corner of the floor and falls asleep.

The spider sets out for the fly; but for his own safety, he does not walk on the floor.

If the room is 40' x 56' with an 8' ceiling, how far must the spider walk for his lunch?

What if the floor is only 4' x 6'?

80.31624 feet

Travels diagonally from the bottom left of the wall, to the top of the wall 8' in (8x8 square) [11.31371 feet] Travels diagonally from 8' into the beginning wall to 8' from the destination wall (32x48 square) [57.68882 feet]. Travels diagonally from 8' from the wall to the corner and eats the fly [11.31371 feet].

If the floor were 4' x 6' the spider would only have to travel 10': Just around the wall.

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The spider will not die of hunger if he goes to the right spots on the walls. As long as I didn't fat finger something in the coding. He has many possibilities to make it there before 82.

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0 13 81.99252496

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I wasn't happy with the "straight up, diagonal across, straight down" approach, it seemed too obvious. So I 'flattened' the room in the attached diagram which now makes it obvious that a different route is shorter.

spiderfly.jpg

Edited by solarfish
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Since the question is "walk", you can subtract 8ft for the spider walking the wall. Being a spider, he could spin a web and lower himself from the ceiling. That makes the answer (to part 1) ~76ft

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I wasn't happy with the "straight up, diagonal across, straight down" approach, it seemed too obvious. So I 'flattened' the room in the attached diagram which now makes it obvious that a different route is shorter.

spiderfly.jpg

You and the good Professor both avoided the 3 4 5 trap that leads to 80 feet.

Good job both. ;)

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Since the question is "walk", you can subtract 8ft for the spider walking the wall. Being a spider, he could spin a web and lower himself from the ceiling. That makes the answer (to part 1) ~76ft

If you were going to allow that then the spider would walk diagonally up the first wall, then diagonally across the ceiling to the corner and then drop down. Which would be 73.75 feet approx.

spiderfly2.jpg

Edited by solarfish
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If you were going to allow that then the spider would walk diagonally up the first wall, then diagonally across the ceiling to the corner and then drop down. Which would be 73.75 feet approx.

spiderfly2.jpg

Joke's on both of you. He's a spider, he doesn't walk, he crawls.

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