## Two Pills

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SchighSchagh
Posts: 24
Joined: Thu Jan 15, 2009 8:16 am UTC

### Two Pills

You have two types of pills that you have to take exactly one of each day. Today, you grab a pill from the first bottle, but when you try to take one from the second bottle, you accidentally pull two pills out, then further spazz so as to drop all three pills (one from the first, two from the second bottle) on the table without knowing which is which. Unfortunately, the pills are unlabelled and look/feel exactly the same. What do you do so as to be certain that you take exactly one of each type of pill without wasting any pills?

Diemo
Posts: 393
Joined: Mon Dec 03, 2007 8:43 pm UTC

### Re: Two Pills

Spoiler:
1) You break the pills in half, take one half of each of the spilled pill and one half from the pill left in the bottle. Repeat the next day.
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SchighSchagh
Posts: 24
Joined: Thu Jan 15, 2009 8:16 am UTC

### Re: Two Pills

Spoiler:
1) You break the pills in half, take one half of each of the spilled pill and one half from the pill left in the bottle. Repeat the next day.

Yup! There are also some variations on that theme that would work.

Do you mind if I ask how long it took you to figure out?

narrativium
Posts: 9
Joined: Fri Sep 12, 2014 11:18 pm UTC

### Re: Two Pills

Spoiler:
Are the pills of a type that can be precisely bisected? My limited understanding of pharmacy is that some pills are containers for the real medicine, the exterior preventing the interior from being exposed/used up too soon in the system; cutting them in half would reduce their effectiveness.

Pseudo-pharmacy aside, 'exactly one' suggests there's a solution which avoids the mess of inexact fractions and deals entirely with integers (where one is good but zero or two are fatal). Admittedly, so far, my only solution is to write three pills off as wasted and hope I can refill a prescription early...

Diemo
Posts: 393
Joined: Mon Dec 03, 2007 8:43 pm UTC

### Re: Two Pills

10 minutes or so
In the beginning the Universe was created.
This has made a lot of people very angry and been widely regarded as a bad move.

Jeff_UK
Posts: 66
Joined: Sat Nov 03, 2007 10:38 pm UTC

### Re: Two Pills

narrativium wrote:
Spoiler:
Are the pills of a type that can be precisely bisected? My limited understanding of pharmacy is that some pills are containers for the real medicine, the exterior preventing the interior from being exposed/used up too soon in the system; cutting them in half would reduce their effectiveness.

Pseudo-pharmacy aside, 'exactly one' suggests there's a solution which avoids the mess of inexact fractions and deals entirely with integers (where one is good but zero or two are fatal). Admittedly, so far, my only solution is to write three pills off as wasted and hope I can refill a prescription early...

Spoiler:
Even if they can be bisected perfectly, the solution also assumes an even distribution of the active ingredient, which is not necessarily the case
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quintopia
Posts: 2906
Joined: Fri Nov 17, 2006 2:53 am UTC
Location: atlanta, ga

### Re: Two Pills

Jeff_UK wrote:
narrativium wrote:
Spoiler:
Are the pills of a type that can be precisely bisected? My limited understanding of pharmacy is that some pills are containers for the real medicine, the exterior preventing the interior from being exposed/used up too soon in the system; cutting them in half would reduce their effectiveness.

Pseudo-pharmacy aside, 'exactly one' suggests there's a solution which avoids the mess of inexact fractions and deals entirely with integers (where one is good but zero or two are fatal). Admittedly, so far, my only solution is to write three pills off as wasted and hope I can refill a prescription early...

Spoiler:
Even if they can be bisected perfectly, the solution also assumes an even distribution of the active ingredient, which is not necessarily the case

Spoiler:
It is USUALLY the case, actually, given the way pills are made, but even if it isn't, no prob bob: weigh the pills, crush them or open them and pour them out (depending on what type they are), mix them yourself, then measure them out again the same way the manufacturer would. This could pose a problem with "coated" tablets in which the medication is not meant to come in direct contact with the stomach lining, but consuming with plenty of water and knowing that you will only be doing it a few times and not repeatedly, you should be fine even then.

Sableagle
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Posts: 1982
Joined: Sat Jun 13, 2015 4:26 pm UTC
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### Re: Two Pills

1) Calm down.
2) Get one pill from each bottle and take them, buying myself 24 hours.
3) Post my problem on a geeks' forum as a logic puzzle and hope they can solve it for me.
Oh, Willie McBride, it was all done in vain.

Exouxas
Posts: 12
Joined: Wed Jan 07, 2015 2:42 pm UTC

### Re: Two Pills

Is this correct? Don't want to look at the spoilers in case I'm wrong :>

Spoiler:
You add one more of the first pill, blend them together and put it back into the pills, then take two of those and save the other two for tomorrow

Fume Troll
Posts: 254
Joined: Wed Jan 13, 2010 8:06 am UTC
Location: Scotland / Norway mainly

### Re: Two Pills

Sableagle wrote:1) Calm down.
2) Get one pill from each bottle and take them, buying myself 24 hours.
3) Post my problem on a geeks' forum as a logic puzzle and hope they can solve it for me.

3) Get more pills one day earlier than planned.