Arsey's D1 Edexcel Summer 2013 Model Solutions BOTH PAPERS

I used the point testing method for question 6, I also wrote 'point testing' just to be clear. Will I loose marks for not drawing the objective line on the graph even though you're only asked to draw the 3 constraints?

Okay so I screwed up Bubble sort and Also I think Kruskal's a few more mistakes I don't think I've gotten lower than 60 though (just playing it safe)

So hopefully that means I've improved on my 50 UMS from January

So what grade boundaries are you guys predicting ???

you really bombed on the bubble sort as that wasn't even on the paper.

you really bombed on the bubble sort as that wasn't even on the paper.

Arsey , for Q 4 i got shortest route 31 and part B 33 i forgot to add 1 path which resulted in 31 instead of 30 but the rest of my values were correct how much will i lose out of 8?

Also for Q5) i used AB 47 not 44 And continued based on that , the rest was correct i suppose , how much will i lose ?

and finally Q 6) i drew 1 inequality wrong so my region looked different but i got the rest of the Question correct how much for that too? sorry to bother you

you really bombed on the bubble sort as that wasn't even on the paper.

can you please have a look at this?

For CA, If I wrote the justification correctly for last part but still had wrong bounds ( cascade still more than lower bound) will I get any marks for last part?

Fairly reasonable paper I thought


1. Matchings - pretty simple, although not breaking down the 2 required paths into separate part of the question, could cause problems.


2. Quick sort and Bin packing - very easy, I thought it was odd how the first-fit decreasing didn't reduce the number of bins though


3. Prim's and Kruskal's - very easy


4. Dikky - harder than normal due to the sneaky part of the route. Quite easy to mank up b) too.


5. Postie - standard. A common error on c) will be to repeat DE.


6. LP - not easy but it never is. Part b) will be a bloodbath.


alt to part b)


no more than 1.5 times as many small as large


for every 3 small you need at least 2 big




7. CPA - Fairly standard but the backward scans not using the dummy paths will be a very common error. Gantt chart took too long. f) and g) will be poorly answered.



Overall I would say it was a little easier than Jan, I would expect it to be around 63 for an A.


This summer I will upload solutions to the following Edexcel papers:

Core 1;
Core 2;
Core 3;
Core 4;
FP1;
M1;
M2;
S1;
D1;
D2.

I will try to get hold of some solutions for FP2; FP3 and M3.

I don't do S2

All papers will be uploaded in line with site rules (please don't PM me asking when I will I be uploading them).

Arsey is it a correct wording to say that

the number of 2 seater boat is at most 3/2 as the number of the 4 seater boat

2

I take it that means you plotted y = x+30 incorrectly

luckily prob just 2

Also, for the linear programming the 2x less than equal 3y..if I put, the number of 4 seater boats must be at least 2/3 of 2 seater boats..is that okay?

thanks arsey and for the prims when I drew it out, I did it correctly like you but I did not put the values just the lines connecting is that okay, there was not enough time

Arsey is it a correct wording to say that

the number of 2 seater boat is at most 3/2 as the number of the 4 seater boat

Arsey, for the gantt question I didn't have enough time to write an explanation but I knew the answer was 5 for the lower bound of workers. Will I still get 1 mark for just putting 5?