Hi sir, I was working a question from my BPP kit on linear programming and there were products A and B. I did the graph but only product A had a demand of 1000 limit. But on my graph I named product B as my X-axis and product A as my Y-axis. Then when I plotted the Demand line, it was a horizontal one instead of vertical(as I used y-axis for A). In the kit, it’s done the opposite way i.e A being x-axis. My question is, is it a fault in the exams?
It does not matter which way round you have your axes. The graph will look different (because it is sort of sideways 馃檪 ) but the final answer will be the same.
I really enjoyed this lecture. Thanks a lot Mr Moffat. I have a question though: Does it matter if Standard or Executive (as in the example) is plotted on the Y axis? Can Executive be on the Y axis also? Thank you.
Just wanted to feed back what a good lecture this is. I was struggling with Linear Programming and this has helped me see things a lot clearer. Fell much better now the penny has dropped!
You can calculate where each 2 lines cross, but if there are more than 2 constraints it will not be obvious without the graph which points are not feasible – I mention this in the lecture.
Also, if the question later mentions that one of the constraints changes, then the effect is more obvious if you have the graph.
Finally, the examiner will ask for the graph and therefore if you have not drawn it you will lose marks!
I think you mean the contribution at each corner of the feasible region (because the lines themselves do not have contributions!).
Assuming that is what you mean, then you can do this and then choose the one with the biggest contribution, However, you must write what you are doing (so the marker is clear) – something like ‘because of the theory of iso-contribution line, I have checked all the corners and the best one is…….’
You must still graph the constraints because it will be asked for, and without it you will not know what the feasible region is. Also, read the question carefully – if it actually asks for the iso-contribution line then obviously you must draw it.
Hi Mr. John, I have a doubt in iso contribution area. That whether it is compulsory that our iso contribution line to be remain in the feasible region area or contribution line can be drawn pass the feasible region.
The iso-profit line is best drawn within the feasible area. (It can be outside, but it makes it easier to make mistakes and choose the wrong point. Also it means that your constraints will not be filling the graph as much as they could have)
Thank you Sir John for this. But during the lecture you said you’ll explain later on how the values were derived for the X-AXIS AND Y-AXIS, giving a maximum value of 40. However, the lecture ended but no explanation was given as to how we derive those values? Could you please explain now. Thanks.
It does not matter what maximum values the axes go up to.
However to make sure that I get a nice big graph, what I do is decide on the points I want to plot for each of the constraints first. Then I fix the scales on the axes to make sure that they are at (or a little above) the maximum I want to plot for x and the maximum I want to plot for y.
This then makes sure that the constraints will actually fit on the graph, and also that they are nice and big 馃檪
Thank you very much! i appeared for my F2 exam in november 2011, my first attempt of F5 will be dis june, dis was a great revision lecture! now i ‘ll move on to the second lecture! Thank u very much sir!
at point A, contribution is $ 216, At point C; contribution is $ 210 and at point B; contribution is $ 225. Thats why we picked point B, because at that point the contribution is the highest (max.) – plz correct me if iam mistaken.
You can check all the corners by all means, however if you draw the iso-contribution line then you can find out from that which is the best corner and then that is all you need to check.
(Checking all the corners is fine, but you must make sure you understand about the contribution line because you just could be asked about it specifically)
Linear programming will certainly come again soon. I think there is a reasonable chance it will be this June, but that is only a guess – you had better make sure you are happy with everything else as well 馃檪
If it does come up in June then it could be either. In the past you have usually been required to draw the graph yourself – the one in 2010 was unusual in that it gave you the graph.
Sir John, Thank you so much for all the resources you and your team have been providing via opentuition. I have one quick question. what is the chance of this area being tested at P5 level.
Firstly, if you do not draw it then you do not know which of the corners of the feasible region is the best. It could be any of them. (OK you could check each of the corners separately, but this would waste time).
Secondly the examiner expects to see it and there will be marks for showing it 馃檪
Mr John, I just want to say that I am having a course with one of ACCA learning partners who has a golden status “i don’t really want to mention the name” and I didn’t understand a word of linear programming!! As I watched your lecture, I think it is one of the easiest topics where I can score marks and I am really hopping it will appear in June’s exams!
Thank you! and btw this is the case with most of F5 lectures, I have to come here to understand the topic! Thanks!
hi mate ..I had a same roblems as yours .. I got not 2 .. video didnt play but download opera from androi market and it plays any video ..my works fine ..pls do so its lovely apps ..thanks
Waal what a great lecture!! this is excellent to say the least, i will definately use open tuition for better results…. thank tutor keep the good work up.
thanxxxxx thanxxxxxxxxxxxxxxx alot , we all love u so much Adim,GOD bless u, i wich every body could think like u this world would be like heavn…………….thanx again
The reason is that we want a ‘big’ graph that fits nicely on the graph paper. The points we need to plot for each line are a maximum for both x and for y of 40 (or close to 40) so if the have the axes going up to 40 then we will get a nice ‘big’ graph. That is all. It doesn’t really matter what your axes go up to, but if the went up to (say) 500 then you would end up with a tiny little graph which would be no use to anyone.
Tyler says
Hi sir, I was working a question from my BPP kit on linear programming and there were products A and B. I did the graph but only product A had a demand of 1000 limit. But on my graph I named product B as my X-axis and product A as my Y-axis. Then when I plotted the Demand line, it was a horizontal one instead of vertical(as I used y-axis for A). In the kit, it’s done the opposite way i.e A being x-axis. My question is, is it a fault in the exams?
Thx 馃檪
John Moffat says
It does not matter which way round you have your axes. The graph will look different (because it is sort of sideways 馃檪 ) but the final answer will be the same.
Jikiboy says
I really enjoyed this lecture. Thanks a lot Mr Moffat. I have a question though: Does it matter if Standard or Executive (as in the example) is plotted on the Y axis? Can Executive be on the Y axis also? Thank you.
John Moffat says
No – it does not matter which axes you use
Jikiboy says
Okay. Thank you very much once again.
Queenie says
Hello
Just wanted to feed back what a good lecture this is. I was struggling with Linear Programming and this has helped me see things a lot clearer. Fell much better now the penny has dropped!
Thank you
Charlotte
Queenie says
*Feel
haha
anam says
Hi! what is the use of graph if we can get reasonable answer by deriving the equations?
John Moffat says
Several reasons!
You can calculate where each 2 lines cross, but if there are more than 2 constraints it will not be obvious without the graph which points are not feasible – I mention this in the lecture.
Also, if the question later mentions that one of the constraints changes, then the effect is more obvious if you have the graph.
Finally, the examiner will ask for the graph and therefore if you have not drawn it you will lose marks!
sky1407 says
Hi sir can i just work out the contribution for each line instead of using the ISO method?must I know both method?
John Moffat says
I think you mean the contribution at each corner of the feasible region (because the lines themselves do not have contributions!).
Assuming that is what you mean, then you can do this and then choose the one with the biggest contribution, However, you must write what you are doing (so the marker is clear) – something like ‘because of the theory of iso-contribution line, I have checked all the corners and the best one is…….’
You must still graph the constraints because it will be asked for, and without it you will not know what the feasible region is.
Also, read the question carefully – if it actually asks for the iso-contribution line then obviously you must draw it.
cool91 says
Hi Mr. John, I have a doubt in iso contribution area. That whether it is compulsory that our iso contribution line to be remain in the feasible region area or contribution line can be drawn pass the feasible region.
Can you please clear my doubt.
Thanks
John Moffat says
The iso-profit line is best drawn within the feasible area. (It can be outside, but it makes it easier to make mistakes and choose the wrong point. Also it means that your constraints will not be filling the graph as much as they could have)
Gabriel says
Thank you Sir John for this. But during the lecture you said you’ll explain later on how the values were derived for the X-AXIS AND Y-AXIS, giving a maximum value of 40. However, the lecture ended but no explanation was given as to how we derive those values? Could you please explain now.
Thanks.
John Moffat says
It does not matter what maximum values the axes go up to.
However to make sure that I get a nice big graph, what I do is decide on the points I want to plot for each of the constraints first. Then I fix the scales on the axes to make sure that they are at (or a little above) the maximum I want to plot for x and the maximum I want to plot for y.
This then makes sure that the constraints will actually fit on the graph, and also that they are nice and big 馃檪
sabaacca says
Thank you very much! i appeared for my F2 exam in november 2011, my first attempt of F5 will be dis june, dis was a great revision lecture! now i ‘ll move on to the second lecture! Thank u very much sir!
chandhini says
Why are we not considering point A? Because A seems to be farthest away from the origin, isnt it? Please reply soon… 馃檪
John Moffat says
Its not just choosing the point furthest from the origin – it is a question of getting the contribution line as far as possible from the origin.
Amanah Saeed says
at point A, contribution is $ 216, At point C; contribution is $ 210 and at point B; contribution is $ 225. Thats why we picked point B, because at that point the contribution is the highest (max.) – plz correct me if iam mistaken.
John Moffat says
You can check all the corners by all means, however if you draw the iso-contribution line then you can find out from that which is the best corner and then that is all you need to check.
(Checking all the corners is fine, but you must make sure you understand about the contribution line because you just could be asked about it specifically)
thusangacca says
i wish linear programming comes this june
John Moffat says
Linear programming will certainly come again soon. I think there is a reasonable chance it will be this June, but that is only a guess – you had better make sure you are happy with everything else as well 馃檪
latoyah says
so John do you think that we may get a graph such as the one on the 2010 paper or we will have to plot the graph
John Moffat says
If it does come up in June then it could be either. In the past you have usually been required to draw the graph yourself – the one in 2010 was unusual in that it gave you the graph.
Surpass says
Sir John, Thank you so much for all the resources you and your team have been providing via opentuition. I have one quick question. what is the chance of this area being tested at P5 level.
John Moffat says
Linear programming is extremely unlikely to be examined in P5.
Surpass says
Just as I thought…Thanks a lot!
Seba says
I am not able to view the videos. It says that there is a server problem. Can I get some help please. I really need to view these.
John Moffat says
The videos are working fine – the problem is likely at your end. Try clicking on the ‘technical support’ tab at the top of this page for suggestions.
opentuition_team says
server problem means that you are most likely behind a firewall. contact your internet provider for help
bisam says
good lecture,but i could’t understand that whether ISO CONTRIBUTION line is necessary to draw or not.
John Moffat says
Yes – you have to draw it for two reasons:
Firstly, if you do not draw it then you do not know which of the corners of the feasible region is the best. It could be any of them. (OK you could check each of the corners separately, but this would waste time).
Secondly the examiner expects to see it and there will be marks for showing it 馃檪
mahoysam says
Mr John, I just want to say that I am having a course with one of ACCA learning partners who has a golden status “i don’t really want to mention the name” and I didn’t understand a word of linear programming!! As I watched your lecture, I think it is one of the easiest topics where I can score marks and I am really hopping it will appear in June’s exams!
Thank you! and btw this is the case with most of F5 lectures, I have to come here to understand the topic! Thanks!
John Moffat says
Thank you very much 馃檪
krischidi says
hello, i have just started using an android device and i cant seem to play the videos. is android not supported?
admin says
Since android out of the box does not support these days flash or mp4
Answer is no
But if you look around android store and download flash player or some browsers many students made it work
So experiment
krischidi says
ok, i’ll try to get round it somehow. many thanks
javid says
hi mate ..I had a same roblems as yours .. I got not 2 .. video didnt play but download opera from androi market and it plays any video ..my works fine ..pls do so its lovely apps ..thanks
takesurechitofu says
Waal what a great lecture!! this is excellent to say the least, i will definately use open tuition for better results…. thank tutor keep the good work up.
jahara420 says
thanxxxxx thanxxxxxxxxxxxxxxx alot , we all love u so much Adim,GOD bless u, i wich every body could think like u this world would be like heavn…………….thanx again
kclsean says
why do we use 40 as max values for X and Y axis ?
aweqib says
because Maximum Production of Standard chair is 40.
Amanah Saeed says
where this is written??
John Moffat says
It is not written, and it is not true 馃檪
The reason is that we want a ‘big’ graph that fits nicely on the graph paper. The points we need to plot for each line are a maximum for both x and for y of 40 (or close to 40) so if the have the axes going up to 40 then we will get a nice ‘big’ graph. That is all. It doesn’t really matter what your axes go up to, but if the went up to (say) 500 then you would end up with a tiny little graph which would be no use to anyone.
fakinboye says
I actually think your lecture is brilliant and its free. I will pay a premium if i have to. Thank you.
ruthany says
ori e
sotor says
John, thank you for the excellent lecture on linear programming, you’ve got Empathy