How can you distribute 20 lbs of pressure in 5 hours using only odd numbers?

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Discussion Overview

The discussion revolves around the challenge of distributing 20 lbs of pressure over 5 hours using only odd numbers. Participants explore the constraints of the problem, including the requirement for each hour to have a positive odd value, and the implications of these constraints on possible solutions.

Discussion Character

  • Debate/contested
  • Mathematical reasoning
  • Exploratory

Main Points Raised

  • Some participants question the clarity of the problem, suggesting it may not make sense as presented.
  • One participant proposes that a solution would require using zero, which is an even number, thus conflicting with the problem's requirements.
  • Another participant argues that a proposed solution takes longer than 5 hours, asserting that it is invalid based on the time constraint.
  • There is a discussion about the interpretation of time measurement, with some suggesting that the solution could technically fit within the 5-hour limit if measured in a specific way.
  • Some participants assert that the requirement for five odd numbers to sum to 20 is impossible, as the product of odd numbers is always even.
  • One participant suggests that the problem allows for values at any point within the hour, which could change the approach to finding a solution.
  • Another participant emphasizes that every hour must have a value, leading to the conclusion that a solution providing six values is invalid.

Areas of Agreement / Disagreement

Participants express disagreement regarding the validity of proposed solutions and the interpretation of the problem's constraints. There is no consensus on a solution, and multiple competing views remain regarding the feasibility of the task.

Contextual Notes

Participants highlight limitations in the problem's phrasing and the assumptions made about time measurement and the nature of odd numbers. The discussion reflects various interpretations of the requirements and the mathematical implications of the constraints.

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Complex Engineering Puzzle!

Distribute 20 lbs of pressure in 5 hours, the numbers Must be Odds and each hour must have a value; you can't use even numbers, nor frations, just positives completes!

which are the values??
 
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I'm sorry, dude, but that question doesn't really make any sense as presented. Can you express it a bit more accurately?
 


errr wouldn't one of the numbers have to be zero for this to work?? otherwise you would always get at least one even number... right?
 


There is not one single answer, but here is one possible answer:
midnight - 1
1 0'clock - 1
2 0'clock - 1
3 0'clock - 1
4 0'clock - 1
5 0'clock - 15
That's an odd number at each hour, and 20 in 5 hours.
NBAJam100, zero is an even number.
 


jimmy,

your solution takes 6 hours (rounding up). There is no solution to this question for 5 hours.
 


You could wait until daylight savings to switch, then 5 hours magically becomes 4 or 6, and you're golden.

Technically, Jimmy's takes 5 hours, not 6 hours, it's just that it doesn't take up a full hour. So he's assuming (for example):

12:30:00 - 1
1:30:00 - 1
2:30:00 - 1
3:30:00 - 1
4:30:00 - 1
5:29:59 - 15

Hence, the "hour" of midnight has 1 in it, and the "hour" of 1 has 1 in it, etc. At least, that's my understanding of his answer.

DaveE
 
Last edited:


junglebeast said:
jimmy,

your solution takes 6 hours (rounding up).
Round down.
 


davee123 said:
You could wait until daylight savings to switch, then 5 hours magically becomes 4 or 6, and you're golden.

Technically, Jimmy's takes 5 hours, not 6 hours, it's just that it doesn't take up a full hour. So he's assuming (for example):

12:30:00 - 1
1:30:00 - 1
2:30:00 - 1
3:30:00 - 1
4:30:00 - 1
5:29:59 - 15

Hence, the "hour" of midnight has 1 in it, and the "hour" of 1 has 1 in it, etc. At least, that's my understanding of his answer.

DaveE
Your solution takes 4 hours, 59 minutes and 59 seconds. Mine takes 5 hours.
 


jimmysnyder said:
Your solution takes 4 hours, 59 minutes and 59 seconds. Mine takes 5 hours.

That gets into the discussion of whether or not you can measure an infinitesemal unit of time, of course-- I was just going by the "normal" measure of time which is to say that since the majority of the full second at 5:30:00 lies AFTER the 5 hour mark, you usually measure the hour to the tail end of the preceeding second. Sort of like why 12:00:00 is PM instead of AM or just "M". The time between the instant it hits 12:00:00 and the instant it hits 12:00:01 is for all intents and purposes 100% (immeasurably smaller) in PM rather than "M", and hence is considered "PM".

But that's just semantics.

DaveE
 
  • #10


jimmysnyder said:
Round down.

The problem specifies that you must do it in 5 hours. Your solution is over the range of [0,5] which takes more than 5 hours, and is therefore an invalid solution. You need a solution that is in the range (0,5) or (0,5] or [0,5).
 
  • #11


junglebeast said:
The problem specifies that you must do it in 5 hours. Your solution is over the range of [0,5] which takes more than 5 hours, and is therefore an invalid solution. You need a solution that is in the range (0,5) or (0,5] or [0,5).

It's not actually taking more than 5 hours-- it's taking *exactly* 5 hours (rounding up or down will yield the same result), and is assuming something that's physically impossible, but mathematically correct. If you imagine a square aligned in the XY plane, for instance, with 1 corner at the origin, and side lengths of 5, the corner on the Y axis isn't at 0,4.9999..., it's at 0,5. So he's basically assuming you can distribute it instantaneously.

DaveE
 
  • #12


jimmysnyder said:
NBAJam100, zero is an even number.


good point... hahaha
 
  • #13


junglebeast said:
The problem specifies that you must do it in 5 hours. Your solution is over the range of [0,5] which takes more than 5 hours, and is therefore an invalid solution. You need a solution that is in the range (0,5) or (0,5] or [0,5).
The length of (0,5), (0,5], [0,5) and [0,5] were all 5 when I went to school.
 
  • #14


There must be a value each hour. But maybe a value anytime. So, it´s easy...
 
  • #15


The riddle is impossible, junglebeast is correct.
The riddle states that every hour must have a value,
This doesn't mean each period of time ending in 00 has a value.

That means every 60 minute interval must have a value.
there are only 5 hours in 5 hours (obviously) thus you must have 5 numbers.
Jimmys solution is providing 6. Thus invalid

The reason it is impossible is, if you must chose 5 numbers that add up to 20 it is impossible without chosing an even number.
Any odd number times an odd number creates an even number, always.
 

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