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## Question

If you're 8 feet away from a door and with each move you advance half the distance to the door.

How many moves will it take to reach the door?

## 14 answers to this question

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If you're 8 feet away from a door and with each move you advance half the distance to the door.

How many moves will it take to reach the door?

Never can reach the door - there will always be a half to infinity!

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Never can reach the door - there will always be a half to infinity!

i heard a very similar one to this in school. " The moon is 384,400km away. The space ship you are traveling in can reach a top speed of 8,400kph. If the space ship you are in traveled half the distance to the moon every day, how long will it take you to get there?"

Both answers are the same. But even when the answer was given to the class, "You will never reach the moon, you will always be halfway there", students still needed some explination.

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If you're 8 feet away from a door and with each move you advance half the distance to the door.

How many moves will it take to reach the door?

This depends on how far you can reach.

1 move-4 ft

2 moves-2 ft

3 moves-1 ft

4 moves-1/2 ft; my arms being longer than 1/2 foot, I can reach the door.

5 moves-1/4 ft

6 moves-1/8 ft

7 moves-1/16 ft, less than an inch, I can now reach the door with a finger, or maybe even my nose

Even though you cannot theoretically never reach the door, in all practical sense, you can, since the distance gets closer to 0 as you get closer to infinity.

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I get the point of the riddle, but looking at it a bit differently, it will take until you arrive at arm's length to reach the door.

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If you're 8 feet away from a door and with each move you advance half the distance to the door.

How many moves will it take to reach the door?

NEVER...

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Can you explain how you get anywhere then? If I'm at work and I want to go to my house 10 miles away, how will I ever get there? First I must go half, and then half of the remaining, and then half of the remaining...

How do I get anywhere?

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Can you explain how you get anywhere then? If I'm at work and I want to go to my house 10 miles away, how will I ever get there? First I must go half, and then half of the remaining, and then half of the remaining...

How do I get anywhere?

You get anywhere by not following the logic of only moving a half the distance at a time. If your house is 10 miles away, then travel 10 miles.

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You get anywhere by not following the logic of only moving a half the distance at a time. If your house is 10 miles away, then travel 10 miles.

But to travel 10 miles I first have to travel 5. And then to travel the remaining 5 miles I first have to travel 2.5 miles. And to travel the remaining 2.5 miles I first must travel 1.25 miles... etc. etc.

So I still shouldn't be able to get anywhere

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But to travel 10 miles I first have to travel 5. And then to travel the remaining 5 miles I first have to travel 2.5 miles. And to travel the remaining 2.5 miles I first must travel 1.25 miles... etc. etc.

So I still shouldn't be able to get anywhere

Why can't you say to travel 10 miles you first need to travel 7? 1? or 10?

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If you're 8 feet away from a door and with each move you advance half the distance to the door.

How many moves will it take to reach the door?

I think I could do this in two moves. You say with each move you advance half the distance to the door. Well if the distance to the door is 8 feet then, half the distance to the door is 4 feet. I'm not going to recalculate the distance every time I move, I'm just going to take it as a given that a move = 4 ft. So, ha! I'm there in two moves.

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I think I could do this in two moves. You say with each move you advance half the distance to the door. Well if the distance to the door is 8 feet then, half the distance to the door is 4 feet. I'm not going to recalculate the distance every time I move, I'm just going to take it as a given that a move = 4 ft. So, ha! I'm there in two moves.

But he says 'with each move you advance half the distance to the door' not half of 8 ft. or half of your starting position.

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It's just a re-worded version of a couple i've seen on here. although i suppoase if you moved once and the door was then opened you could make it in one move. i never said anything about the door not being opened or not being moved closer just because we know what the answer should be doesn't mean we should not try and find a way round it. "by attempting to break the bonds of our realtiy we alter the reality and because of the ability to alter our own reality then all the infinities of the universe or ours to behold" If you haven't guessed by now i really like sayings and quotes that one though was all me YAY me lol

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Are you two a double act?

Noct, get itachi-san to take you home if he is willing - I know a short cut though.

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What is with you?? I've seen a few of your posts today and you seem to be getting very angry and personal towards people, however does your wife put with it Mr. Frederick Burkert?? It's not nice when people do it back to you NOW IS IT??

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