A rude security guard

Question

I was walking down a street, when I see a door, with a security guard.

A man approaches him, and the guard flips a middle on him.

"Well that escalated quickly." you think.

The man, unfazed, replied "4."

The guard allowed him to pass.

When another man approaches, the guard did not stick one, but two middle fingers.

The second man now replies, "132."

At this time, you are completely bewildered.

You decide to approach the guard. He looks at you, and he throws both pinkies up, and sticks them together.

What do you say?

Alternatively, you could flip someone of with the middle finger and the thumb, or the UK way, with the index and the rim, for ulterior puzzles — GettnDer, Jan 04 '17 at 21:54

DooplissForce · Accepted Answer · 2016-12-28T18:44:44.000

85

You say

$48$,

because

the guard's fingers represent binary digits. Let the right thumb represent $2^0 = 1$, the right index finger represent $2^1 = 2$, and so on (see diagram). When a finger is extended, it represents a $1$ in that position, and an unextended finger represents a $0$.

Therefore, since the right middle finger represents $2^2=4$, the first man answers $0000000100_2=4_{10}$. The left middle finger represents $2^7=128$, thus two middle fingers represent $0010000100_2 = 132_{10}$, the second man's answer. You see the left and right pinkies extended, thus you answer $48$, since $0000110000_2=48_{10}$.

edited Dec 28 '16 at 18:44

answered Dec 28 '16 at 18:35

DooplissForce

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Enjoy your 2k privileges :-)! – IAmInPLS Dec 28 '16 at 19:13
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Seems fitting if you could get to 2048 reputation for this answer. – YowE3K Dec 28 '16 at 19:17
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@YowE3K Currently 2049. Doopliss, go and downvote an answer ;-) – Rand al'Thor Dec 28 '16 at 19:28
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@randal'thor I'll go downvote one of yours ;) – DooplissForce Dec 28 '16 at 19:30
@Doopliss I'll upvote yours, to remove the temptation ;-) (actually not for that reason, but because it's a nice answer to a nice puzzle) – Rand al'Thor Dec 28 '16 at 19:31
@randal'thor Too late ;) (But thank you!) – DooplissForce Dec 28 '16 at 19:33
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@Doopliss Who is the shooter? It'll be me if you don't watch out! :-P – Rand al'Thor Dec 28 '16 at 19:35
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Enjoy your (?) Third time's a Charm – bleh Dec 29 '16 at 14:19
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@randal'thor I was hoping you would go with the 4, 128 threat, but you didn't. :P (Those of you that still don't get it: look at the picture in the answer.) – Anonymous Penguin Dec 30 '16 at 03:48
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Whoa, what a binary treat :D – ABcDexter Dec 30 '16 at 13:34

score 0 · Answer 2 · edited Dec 30 '16 at 12:27

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My answer

48

My reasoning is that the guard must be using a code and I need to crack it as follows.

The guard's questions are all powers of 2 indicated by fingers. The first question was $2^2+0^1+0^0$. Correct answer was given, $4+0+0=4$. The 2nd question was $2^7+2^2$. Correct answer was given, $128+4=132$. So my question was $2^5+2^4$. Gives, $32+16=48$.

QED

edited Dec 30 '16 at 12:27

Beastly Gerbil

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answered Dec 30 '16 at 12:03

MikeRoger

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So this is what the accepted answer says? – Beastly Gerbil Dec 30 '16 at 12:27

A rude security guard

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