[Archive!] Pure mathematics, physics, chemistry, etc.: brain-training problems not related to trade in any way - page 504

 
Mathemat:
The problem also shows that it is not necessary that U1>U0. It can also be less.

No, it says change, which is what it means, a change in voltage in one element can cause a bigger change in the other element, from which the gain derives.
 

From matforum:

A hockey team has 6 players (5 field players and a goalie) and their jerseys have numbers on them: 1, 2, 3, 4, 5 and 6.
If the players line up, you get a six-digit number (for example, 345126).
Call numbers of this kind hockey numbers.
Can one hockey number be divided evenly by another?

 
Mathemat:

From matforum:

A hockey team has 6 players (5 field players and a goalie) and their jerseys have numbers on them: 1, 2, 3, 4, 5 and 6.
If the players line up, you get a six-digit number (for example, 345126).
Call numbers of this kind hockey numbers.
Can one hockey number be divided evenly by another?

I'd write a program to solve this problem! :D But for now I'm trying to apply logic.
 
I can write it too. It's OK, even if the calculations are sub-optimal (there aren't many of them here). Still, it is really better to think with a pen in hand.
 
Mathemat:

From matforum:

A hockey team has 6 players (5 field players and a goalie) and their jerseys have numbers on them: 1, 2, 3, 4, 5 and 6.
If the players line up, you get a six-digit number (for example, 345126).
Call numbers of this kind hockey numbers.
Can one hockey number be divisible by another?

At first I tried to solve the problem head-on, but it took me a long time (it took me about 2 hours). But it became clear that most of the variations of hockey numbers fall out, but still there is a considerable amount left to solve the problem head-on.

The maximum integer that is possible (or impossible) to get by dividing one hockey number by another is 5, the minimum is 2.

I decided to write down division variants (simple ones to begin with) that are possible to make from the given numbers:

2/2 = 1
4/2 = 2
6/2 = 3
12/2 = 6
...

3/3 = 3
6/3 = 2
12/3 = 4
15/3 = 5
...

4/4 = 1
12/4 = 3
24/4 = 6
...

5/5 = 1
15/5 = 3
25/5 = 5
...

Variants with a common divisor are grouped together.

I noticed that each such group has a pair of numbers or even a triplet of hockey players' numbers, which is problematic to obtain and began to doubt that it is even possible. But this reasoning is clearly not enough to solve the problem.

And to understand this, you need to make more complex variants of division. Once again, it turns out to be a head-to-head solution...

After that my hands were empty. I will think more at my leisure, maybe some idea will come to mind.

 
When multiplied, the sum of the numbers should not change.
 
MaxZ:
I don't get it. How much are we talking about?
The sum of the numbers.
 
MetaDriver:
About the sum of the numbers.

Got it. Not in time! :))))


TheXpert:
When multiplied, the sum of the numbers should not change.

Is it just a thought? Or the way in which the problem is solved?

 

the result of division necessarily equals 3.

if, of course, the problem is solvable.

Just kidding, though. :)

rather the opposite - the result cannot be a 3.

 
MetaDriver:

The result of division is necessarily 3.

if, of course, the problem is solvable.

Just kidding, though. :)

rather the other way round - the result cannot be a 3.

You want to confuse everyone? :)))

I've gone all the way through the five... :D I couldn't find any hockey numbers like that. Many, as I wrote above, fall out.

But it's not an easy task to solve. I stopped at this one. And I solved it in two ways (division and multiplication), I thought I would find something in it.

Reason: