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

In summary, Jimmy's solution takes 6 hours, but the problem specifies that you must do it in 5 hours. His solution is therefore invalid.
  • #1
reinaldo
33
0
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!

wich are the values??
 
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  • #2


I'm sorry, dude, but that question doesn't really make any sense as presented. Can you express it a bit more accurately?
 
  • #3


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?
 
  • #4


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.
 
  • #5


jimmy,

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


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:
  • #7


junglebeast said:
jimmy,

your solution takes 6 hours (rounding up).
Round down.
 
  • #8


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.
 
  • #9


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.
 

What is a Complex Engineering Puzzle?

A Complex Engineering Puzzle is a problem or challenge that requires advanced knowledge and skills in engineering to solve. It often involves multiple components, variables, and constraints that need to be carefully considered and integrated in order to come up with a successful solution.

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Complex Engineering Puzzles push the boundaries of what is currently possible and drive innovation in the field of engineering. By solving these puzzles, engineers are able to develop new technologies and solutions that have real-world impact and improve our lives.

What are some examples of Complex Engineering Puzzles?

Examples of Complex Engineering Puzzles include designing and building a self-driving car, creating a sustainable energy source, or developing a complex medical device. These puzzles often require a multidisciplinary approach and collaboration among different engineering fields.

What skills are needed to solve Complex Engineering Puzzles?

Solving Complex Engineering Puzzles requires a strong foundation in mathematics, physics, and other sciences, as well as critical thinking, problem-solving, and creativity. It also requires excellent communication and teamwork skills, as many puzzles are too complex for one person to solve alone.

How can one improve their skills in solving Complex Engineering Puzzles?

One can improve their skills in solving Complex Engineering Puzzles by continuously learning and staying updated on the latest advancements and techniques in their field of engineering. Engaging in hands-on projects, collaborating with other engineers, and seeking mentorship from experienced professionals can also help in developing problem-solving skills.

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