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## Question

1. A man walks up an up escalator at 1step per second it takes him 20 steps to reach the top.

The next day he walks up at 2 step per second it takes him 32 steps to reach the top.

How many steps in the escalator?

2. a

? b

b ? c

+ a ? c

----------------

c ? c

Only three numbers, all positive, what is the um and the values for a,b,c.

3. A____I__________B

Form A to B is a bridge.

A man (I) is 3/8 of the way from point A when he hears a train going 60 mph approaching point A.

If he runs to point A he will meet the train at A, if he runs to point B the train will catch him at point B.

How fast does he run?

4.(a classic)

There are three towns

Nobleland- Truth tellers

Liarsville- (guess)

Wishiywashy Town- Say truth lie alternatively eg LTLT or TLTL but you do not know which they will start on.

Three people George, Bob and Fred.

They are each from one town.

They sit as pictured

G

B F

1. Where is person on left from?

2. Where is person on right from?

3. Where are you from?

G: 1.LiarsVille

2. Wishywashy

3. Nobleland

F. 1. Wishywashy

2. Wishywashy

3. Nobleland

B. 1. Liarsville

2. Nobleland

3. Nobleland

Where are F, G,B from?

I know the answer for 2 and can debate on all but 1.

## Recommended Posts

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grr puzzle formatted wrong

column

123

in column 1 the bottom 2 places have a then b

in column 2 the three are ??? with answer ?

and in column 3 it is a then b then c then c with answer c

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B & G are Wishy Washy

F is from Nobleland

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No.

The are each from a distinct town. No towns have 2 people at the table.

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Just wondering on #4 are they sitting in a circle and when asked about the person on the left is it that persons left or is it to your left.

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If they are sitting in a circle and when they are asked the question it is about the person to the right or left of the person you are asking the question to then...

G has to be the truth teller because he is the only one that gave an answer of one person in each town. So B is Wishy washy and F is liar, according to G who tells the truth.

But if thats not the case then I need to think about it a bit more. Thanks for the puzzles!

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The answer to number three is:

fifteen miles per hour, because the man runs a fourth of the way across the bridge during the time the train crosses the bridge.

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as fast as he can!!!

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I assumed that it was the respondents right and left.

Dan: That`s what i got.

Nesto: That's mostly my logic, im not sure if it is 100% right thou. And thank you.

Dragon: lol just saw you posted as i am sure you are aware that is wrong, but i actually think the true only correct answer is...

he jumps off the bridge.

Edited by Ventum
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As hard as I might find it to run that fast, I must say, I believe GrouchyDan is right.

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No.

The are each from a distinct town. No towns have 2 people at the table.

if they are all from different towns, then clearly G has to be the truth teller since he named all three towns...that makes F a liar and B a wishywashy...however, if u see F's answers, he says the person on his left i.e B is wishywashy which is true but F can't speak the truth so this is a contradiction.. I don't know what am I missing...

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No.

The are each from a distinct town. No towns have 2 people at the table.

also, if there can be more than one from same town, then jbk's solutions seems to work because the wishywashy guys are always telling truth and lie in LTL pattern coz' their 3rd statement is always false..

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80

total steps = X

rate of elevator = E steps/s

t1=20s

t2=16s

r1=1 steps/s

r2=2 steps/s

r*t=d

(r1+E)t1=X

(r2+E)t2=X

(1+E)20=X

(2+E)16=X

20+20E=X

32+16E=X

20+20E=32+16E

20E-16E=32-20

4E=12

E=3 steps/s

(1+E)20=X

(4)20=X

80=X

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Zeppo: that is the conclusion i arrived at as well.

Oh and a new one:

from this point on ~ will equal square root

X=~1+~1+~1+~1+~1+~1+~1+...

What is X?

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it might not have been clear but the expression meant the square root of ( one plus the square root of ( one plus the square root of ( one plus etc.

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Got there a little differently and don't think it's right.

On day one, it takes 20 seconds to reach the top (1 step per second and 20 steps were taken)

So, On day 2, I figured that the time to the top is still 20 seconds. At 2 steps per second, he would go 40 steps.

I suppose you could assume that the escalator is a belt so that if there are 20 onthe top, then there would be twenty or so underneath.

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Got there a little differently and don't think it's right.

On day one, it takes 20 seconds to reach the top (1 step per second and 20 steps were taken)

So, On day 2, I figured that the time to the top is still 20 seconds. At 2 steps per second, he would go 40 steps.

I suppose you could assume that the escalator is a belt so that if there are 20 onthe top, then there would be twenty or so underneath.

You need to factor in the fact that you add the rate of the elevator to your rate of climb, your logic works well on a stationary elevator though. Mitch Hedberg quote "An escalator can never break, it can only become stairs." R.I.P.

And Ventum, I kinda see where you went, but have a few too many beers in me to follow all the way.

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Zeppo: that is the conclusion i arrived at as well.

Oh and a new one:

from this point on ~ will equal square root

X=~1+~1+~1+~1+~1+~1+~1+...

What is X?

Pretty much any number you want, since ~1 = 1 or -1...so you can use any combination of these to get any number from -infinity to +infinity...

for example, to get negative infinity, you just say all ~1 = -1...to get 0 you would just alternate each ~1 with +1 and -1...to get +infinity, you would just say all ~1 = 1...you can then get any number in between by simply adding the correct number of +1 or -1 to get to the number you want, and then just start alternating +1/-1 from then on (so you are essentially adding 0)

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Pickett: You misunderstand me. I mean the quantity of so you will take square root of 1(one) and and this to the square root of 1 to get 2 then square root 2 and and square root 1 and so forth to infinity, how big is x?

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I'm still thinking about the first one. I just don't see (yet?) how he can go faster on the second day and require more steps for the same escalator (unless the escalator is moving at different speeds on different days...)

For 2: are all values supposed to be distinct?

```   a
?b
b?c
+a?c
----
c?c[/codebox]```

[spoiler=my answers so far]2) Assuming all a, b, c are unique natural numbers and ? means any number, a = 2, b= 3, c = 5 would work. Or, swap a & b. The constraint is that a + b + c has to end in 0, and a + b should be <= c.

[codebox] 2
13
315
+215
----
545

3) This is not possible to answer because there is no indication of how far the train is from point A and what vectors bring it to A or B. If it is on a circular track that includes A and B, then it will eventually come back around to both...

4) I don't see how this one can be solved because both Fred and Bob are saying two people are from the same town. That would mean neither is telling the truth, so it would have to be that George is the truth-teller. But then his statement that Fred is a liar/Bob is wishywashy would make Fred's statement that Bob is wishywashy true, which is not possible.

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Not sure why I can't edit my posts, because I know I've done it before.

Anyway, I read Zeppo's answer for #1 and understand the wording better now. You mean he moved a distance of 1 step plus elevator movement per second on the first day and likewise 2 steps plus elevator movement on the second day. I agree with Zeppo's answer and calculation.

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Since the escalator is a belt with no end, wouldn't there be infanite stairs?

15 mph

Edited by kkehoe5
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Jb: I agree with your answer to number two, your reasoning is incorrect on number 3 however.

kkehoe: while technically the escalator has infinite stairs, the spirit of the question is how many stairs in one full revolution of the escalator belt.

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Jb: I agree with your answer to number two, your reasoning is incorrect on number 3 however.

OK, I don't know what I was thinking with the distance to A part, but the vector to B is important. Assuming the train travels in a straight line from A to B at a constant 60 mph, I agree with other posters.

The person at I has to run 3/8 of the bridge to get to A or 5/8 to get to B. This means that if he starts running straight to B, then when the train reaches A, he will only have 2/8 or 1/4 of the bridge left to go. IF the train goes straight from A to B, then the man needs to run 1/4 the train's speed in order to reach B at the same time. 1/4 x 60mph = 15mph.

Any thoughts on my comments about the 4th puzzle? I can explain more if it's unclear.

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Very good, no answers to the square root one yet.

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i can only imagine he went up the down escalator the second day and there has to be at least 32 steps probable twice as much due to conveyer.

1. A man walks up an up escalator at 1step per second it takes him 20 steps to reach the top.

The next day he walks up at 2 step per second it takes him 32 steps to reach the top.

How many steps in the escalator?

2. a

? b

b ? c

+ a ? c

----------------

c ? c

a=2,b=3,c=5

2

+3

3+5

+2-5

------

5+5

Only three numbers, all positive, what is the um and the values for a,b,c.

3. A____I__________B

Form A to B is a bridge.

A man (I) is 3/8 of the way from point A when he hears a train going 60 mph approaching point A.

If he runs to point A he will meet the train at A, if he runs to point B the train will catch him at point B.

How fast does he run?

it depends on the trains starting point and why bother hes dead either way and why not just climb over the railing of the bridge till it passes.

4.(a classic)

There are three towns

Nobleland- Truth tellers

Liarsville- (guess)

Wishiywashy Town- Say truth lie alternatively eg LTLT or TLTL but you do not know which they will start on.

Three people George, Bob and Fred.

They are each from one town.

They sit as pictured

G

B F

1. Where is person on left from?

2. Where is person on right from?

3. Where are you from?

G: 1.LiarsVille

2. Wishywashy

3. Nobleland

F. 1. Wishywashy

2. Wishywashy

3. Nobleland

B. 1. Liarsville

2. Nobleland

3. Nobleland

Where are F, G,B from?

G is from Nobeltown

F is from Wishywashy town

B is from Liarsville

I know the answer for 2 and can debate on all but 1.

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