in a Room of 100 people, 99% of them are Spinkos. ...

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henh...@gmail.com

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Sep 23, 2022, 3:15:13 PMSep 23
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------ pls wait 3+ days (Longer if you find it easy or trivial) before posting answers or hints.


1. in a Room of 100 people, 99% of them are Spinkos.
How many ppl must leave the room
to bring down the percentage of Spinkos in the room to 98% ?


2. in a Room of 1000 people, 99% of them are Spinkos.
How many ppl must leave the room
to bring down the percentage of Spinkos in the room to 98% ?


if you don't like the (label) [Spinkos], pls suggest a more acceptable term. Thanks.


__________________________
in Finnish, a PINKO is a Synonym of hikipinko (“studious student”).
https://en.wiktionary.org/wiki/hikipinko#Finnish

-------------- a [Plodder] in Brit.English ?


William Shakespeare, “Loues Labour’s Lost”

[Act I, scene i]:
Study is like the heaven’s glorious sun
That will not be deep-search’d with saucy looks:
Small have continual plodders ever won
Save base authority from others' books

----------- i don't get these lines.

Edward Murphy

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Sep 25, 2022, 5:42:27 PMSep 25
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On 9/23/2022 12:15 PM, henh...@gmail.com wrote:

> ------ pls wait 3+ days (Longer if you find it easy or trivial) before posting answers or hints.
>
>
> 1. in a Room of 100 people, 99% of them are Spinkos.
> How many ppl must leave the room
> to bring down the percentage of Spinkos in the room to 98% ?
>
>
> 2. in a Room of 1000 people, 99% of them are Spinkos.
> How many ppl must leave the room
> to bring down the percentage of Spinkos in the room to 98% ?

[spoiler space]































1. 99% Spinkos = 1% non-Spinkos
98% Spinkos = 2% non-Spinkos

Interpreting "must" as looking for the minimum, we want the same set
of non-Spinkos to become twice as much of a percentage of the total,
so the total must become half its original value, i.e.

Start with 99 Spinkos, 1 non-Spinko (99 is 99% of 100, 1 is 1%)
50 Spinkos leave (this is the answer sought)
End with 49 Spinkos, 1 non-Spinko (49 is 98% of 50, 1 is 2%)

2. By the same argument, the minimum is for 500 Spinkos to leave.

If it doesn't need to be the minimum, then we can optionally have up
to nine additional sets of people leave, where each of these sets
includes 49 Spinkos and 1 non-Spinko. (This wasn't an option for #1,
as such a set leaving would leave zero people in the room.)

henh...@gmail.com

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Sep 25, 2022, 7:59:52 PMSep 25
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On Friday, September 23, 2022 at 12:15:13 PM UTC-7, henh...@gmail.com wrote:
> ------ pls wait 3+ days (Longer if you find it easy or trivial) before posting answers or hints.
>
>
> 1. in a Room of 100 people, 99% of them are Spinkos.
> How many ppl must leave the room
> to bring down the percentage of Spinkos in the room to 98% ?
>
>
> 2. in a Room of 1000 people, 99% of them are Spinkos.
> How many ppl must leave the room
> to bring down the percentage of Spinkos in the room to 98% ?
>
>
> if you don't like the (label) [Spinkos], pls suggest a more acceptable term. Thanks.


the real puzzle is... Can you tweak the problem(s) slightly so that
it becomes much more tricky and interesting ?



> __________________________
> in Finnish, a PINKO is a Synonym of hikipinko (“studious student”).
> https://en.wiktionary.org/wiki/hikipinko#Finnish
>
> -------------- a [Plodder] in Brit.English ?
>
>
> William Shakespeare, “Loues Labour’s Lost”
>
> [Act I, scene i]:
> Study is like the heaven’s glorious sun
> That will not be deep-search’d with saucy looks:
> Small have continual plodders ever won
> Save base authority from others' books
>
> ----------- i don't get these lines.


i was confused for a few hours because
i could only think of Sun's (light) rays as
doing the searching and glaring and looking.
(not the other way around)

Anton Shepelev

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Sep 27, 2022, 12:54:43 PMSep 27
to
Hen Hanna to himself:

> > [Act I, scene i]:
> > Study is like the heavenТs glorious sun
> > That will not be deep-search'd with saucy looks:
> > Small have continual plodders ever won
> > Save base authority from others' books
> >
> > ----------- i don't get these lines.
>
> i was confused for a few hours because
> i could only think of Sun's (light) rays as
> doing the searching and glaring and looking.
> (not the other way around)

Now you know the meaning of passive voice.

riverman

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Nov 13, 2022, 10:07:17 AMNov 13
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Yes. What if the people leave randomly, rather than exclusively selecting non-Spinkos?

Edward Murphy

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Nov 13, 2022, 5:11:11 PMNov 13
to
On 11/13/2022 7:07 AM, riverman wrote:

> On Monday, September 26, 2022 at 7:59:52 AM UTC+8, henh...@gmail.com wrote:

>> On Friday, September 23, 2022 at 12:15:13 PM UTC-7, henh...@gmail.com wrote:

>>> ------ pls wait 3+ days (Longer if you find it easy or trivial) before posting answers or hints.
>>>
>>>
>>> 1. in a Room of 100 people, 99% of them are Spinkos.
>>> How many ppl must leave the room
>>> to bring down the percentage of Spinkos in the room to 98% ?
>>>
>>>
>>> 2. in a Room of 1000 people, 99% of them are Spinkos.
>>> How many ppl must leave the room
>>> to bring down the percentage of Spinkos in the room to 98% ?

>> the real puzzle is... Can you tweak the problem(s) slightly so that
it becomes much more tricky and interesting ?

> Yes. What if the people leave randomly, rather than exclusively
selecting non-Spinkos?

Or exclusively selecting Spinkos, rather.

Anyway, the minimum number possible is the same as if only non-Spinkos
are selected, and the maximum number possible is whatever brings the
number of non-Spinkos down to exactly 1. It's also possible to fail to
hit the desired new percentage entirely, if the last non-Spinko is
removed before it's hit.

What's the average number, if we discard those failures? If the minimum
and maximum are equal, then obviously it's that number. Otherwise, it's
a question of which specific totals (of Spinkos and non-Spinkos removed)
are possible, how many ways there are to reach each one, and how many of
those ways also hit the percentage at some earlier point first.

leflynn

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Nov 16, 2022, 7:03:57 PMNov 16
to
On Sunday, November 13, 2022 at 5:11:11 PM UTC-5, Edward Murphy wrote:
> On 11/13/2022 7:07 AM, riverman wrote:
>
> > On Monday, September 26, 2022 at 7:59:52 AM UTC+8, henh...@gmail.com wrote:
>
> >> On Friday, September 23, 2022 at 12:15:13 PM UTC-7, henh...@gmail.com wrote:
>
> >>> ------ pls wait 3+ days (Longer if you find it easy or trivial) before posting answers or hints.
> >>>
> >>>
> >>> 1. in a Room of 100 people, 99% of them are Spinkos.
> >>> How many ppl must leave the room
> >>> to bring down the percentage of Spinkos in the room to 98% ?
> >>>
> >>>
> >>> 2. in a Room of 1000 people, 99% of them are Spinkos.
> >>> How many ppl must leave the room
> >>> to bring down the percentage of Spinkos in the room to 98% ?
> >> the real puzzle is... Can you tweak the problem(s) slightly so that
> it becomes much more tricky and interesting ?
> > Yes. What if the people leave randomly, rather than exclusively
> selecting non-Spinkos?

Reminds me of the fruit drying problem. You have ten pounds of fruit. It is 99% water.
How much does it weigh when you have dried it out so that it is 95% water.
L. Flynn
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