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Reply 80
i dont get how it was 450 when STRINGS added up to 454

and i got 1200... but that was just the total taken not the profit :frown:
STRINGS added up to 450 for me.
Reply 82
bugger
I got 450 for the upper bound and 425 for the lower bound.
For profit i got something like 1185.

x=320
y=50

so y and z =25 i think

I had the O line as P=3x + 4.45 y
cos it was P=3x + 2.25y +2.25 z and y=z so i got the above formula.

But I was in a hurry and didnt read the question right so i got the line wrong i think. But i did put it equal to 450.
Reply 85
Smeghead UK
For profit i got something like 1185.

x=320
y=50

so y and z =25 i think

I had the O line as P=3x + 4.45 y
cos it was P=3x + 2.25y +2.25 z and y=z so i got the above formula.

But I was in a hurry and didnt read the question right so i got the line wrong i think. But i did put it equal to 450.


Yes I got the same thing as you! Good :smile:

I couldn't do the last question, but I think I could do everything else, so I'm pleased :smile: I can't remember the upper and lower bounds questions that well though, I think I got similar/the same answers as what some other people posted. It wasn't a bad test so I'm pleased...I think.

Does anyone know how many times the vertex F (I think? It was in the Chinese Postman question, after Dijkstra), the tour from N in the Nearest Neighbour question and the degree of the node in the last question?
Reply 86
I think the tour went through F 4 times, could be wrong though :smile: , and the degree of the node in the last question was between 1 and 5, x was 4 i believe
Reply 87
Smeghead UK
For profit i got something like 1185.

x=320
y=50

so y and z =25 i think

I had the O line as P=3x + 4.45 y
cos it was P=3x + 2.25y +2.25 z and y=z so i got the above formula.

But I was in a hurry and didnt read the question right so i got the line wrong i think. But i did put it equal to 450.




What did you all get for the optimum price and the values of x,y & z in the linear programming question?
I see a few people got Β£180-190, 315-325(x), 25(y,z)
I got Β£185 for max profit & x=320, y,z=50

5x+4y+4z<=2000 putting my values into this would give a maximal value, unless my equation is wrong?.
It also may be worth noting that two of the equalities were y>=50 & z>=50, so 25 isn't even feasible!
Reply 88
rob...
What did you all get for the optimum price and the values of x,y & z in the linear programming question?
I see a few people got Β£180-190, 315-325(x), 25(y,z)
I got Β£185 for max profit & x=320, y,z=50

5x+4y+4z<=2000 putting my values into this would give a maximal value, unless my equation is wrong?.
It also may be worth noting that two of the equalities were y>=50 & z>=50, so 25 isn't even feasible!


I agree, x=320, y=50, z=50, profit=Β£185

What was your profit line though? I got 'Maximise: 2x+y' although I wasn't sure....
Reply 89
Lox352
I agree, x=320, y=50, z=50, profit=Β£185

What was your profit line though? I got 'Maximise: 2x+y' although I wasn't sure....


I got P=0.5x+0.5y?

This was after:
P=(3-2.5)x + (2.25-2)y + (2.25-2)z
P=0.5x+0.25y+0.25z & y=z
P=0.5x+0.5y
I should really stop reading this thread... it's throwing doubt into some of my answers....
Reply 91
rob...
I got P=0.5x+0.5y?

This was after:
P=(3-2.5)x + (2.25-2)y + (2.25-2)z
P=0.5x+0.25y+0.25z & y=z
P=0.5x+0.5y


Yes, that seems logical.

This was my logic.

Profit for x=0.5
Profit for y=0.25
Profit for z=0.25
Profit fo x= 2 X profit for y & z
Thus, Maximise 2x+y
Reply 92
Lox352
Yes, that seems logical.

This was my logic.

Profit for x=0.5
Profit for y=0.25
Profit for z=0.25
Profit fo x= 2 X profit for y & z
Thus, Maximise 2x+y


It's interesting that we both got the same answer! Hopefully the marker won't bother paying too much attention to our objective lines and just mark us right for the 185,320,50,50 :P
Reply 93
rob...
It's interesting that we both got the same answer! Hopefully the marker won't bother paying too much attention to our objective lines and just mark us right for the 185,320,50,50 :P


I also got Β£185 profit... though no-one else in my school realised to take cost off.
I did it a wrong way by making the objective function line equal to the pure profits:
P=3x+4.5y - working out the total income and then taking that away from his initial costs (Β£1000).

But as you say I think they will look for the 320, 50, 50 and Β£185.. though I will probably have lost a mark in the question before where it asked you to draw on the line.
Oh well... better than everyone else who took the exam!
Reply 94
for the dijskars did anyone get 48 or 49, can't remember which I got..
Reply 95
Bently7
I also got Β£185 profit... though no-one else in my school realised to take cost off.
I did it a wrong way by making the objective function line equal to the pure profits:
P=3x+4.5y - working out the total income and then taking that away from his initial costs (Β£1000).

But as you say I think they will look for the 320, 50, 50 and Β£185.. though I will probably have lost a mark in the question before where it asked you to draw on the line.
Oh well... better than everyone else who took the exam!


Hopefully you'll just get an incredibly bored examiner, who can't be bothered to check through your working then :P

Decision 2 on Thursday! :woo:
NOT!
Reply 96
Jfranny
for the dijskars did anyone get 48 or 49, can't remember which I got..


I think the Dijkstra's one didn't specify an end vertex; it only wanted you to label the vertices with the minimum distance from "M"? as far as I remember...
rob...
I think the Dijkstra's one didn't specify an end vertex; it only wanted you to label the vertices with the minimum distance from "M"? as far as I remember...

I think he means to B. I think I got 49 as well.
Reply 98
rob...
Hopefully you'll just get an incredibly bored examiner, who can't be bothered to check through your working then :P

Decision 2 on Thursday! :woo:
NOT!


Woah, woah, woah... isn't D2 on Friday?!?!?!
Reply 99
Bently7
Woah, woah, woah... isn't D2 on Friday?!?!?!


Yes sorry, is tomorrow :P

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