Formulate this as a linear programming problem

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SUMMARY

The discussion focuses on formulating a linear programming problem involving desktop and pocket diaries, specifically defining the relationship between the two variables, ##x## (desktop diaries) and ##y## (pocket diaries). The key constraint established is that the number of pocket diaries must be at least twice the number of desktop diaries, represented mathematically as ##y \geq 2x##. Additionally, the conversation touches on the application of Kruskal's algorithm in the context of minimum spanning trees, clarifying that cycles must be avoided while ensuring that edges can intersect without forming loops.

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chwala
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Homework Statement
See attached: this decision maths text book I realized has a number of wrong notations and solutions in various topics:critical path etc

Just counter check the phrase "twice as many pockets as desktop"

Is that correct? Is it not firstly, ##2y=x##
Relevant Equations
Decision maths
See attached ...
 

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I believe ##x## is used for desktop diaries and ##y## is used for pocket diaries.

They key word is “at least”

“They will need at least twice as many pocket diaries as desktop diaries”……translation: “the number of pocket diaries must be greater than or equal to 2 times the number of desktop diaries”

So

##y \geq 2x##
 
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And this one, sorry, am using phone to type...
Number 2,
For kruskal algorithm, CE shouldn't be connected as it forms a cycle, correct? ...or a cycle refers to connected vertices? am I missing something. See my sketch...
 

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Last edited:
chwala said:
Just counter check the phrase "twice as many pockets as desktop"

Is that correct? Is it not firstly, ##2y=x##
The phrase “there is twice as many ## y ## as ## x ##” means ## y=2x ##.
 
chwala said:
...or a cycle refers to connected vertices?
Yes, it does.

The edge CE is included into the minimum spanning tree too.
 
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Gavran said:
Yes, it does.

The edge CE is included into the minimum spanning tree too.
I thought CE shouldn't be connected as shown on text, as that does not conform to the kruskal algorithm. I stand to be corrected.

Just seen that intersection can occur as long as the vertices are not connected to form loop, in that case the textbook is correct. Cheers man.
 
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