Further Math Exam 1: Answers + Discussion!

[Amber Holmes]

I think Question 6 in core is E as there are 3 outliers in the data and option A only has 2!

[Dan1995]

I think Question 6 in core is E as there are 3 outliers in the data and option A only has 2!

That question has been discussed many times now, the general consensus is still A. As the lower median is 30, and the upper is 50. Therefore q3+1.5xIQR =50+1.5x(50-30)=80. Therefore there's only two outliers.

[megannn]

Can someone please explain Que 8 networking, why is E the correct answer? like why are the others false? 

[Dan1995]

Can someone please explain Que 8 networking, why is E the correct answer? like why are the others false?

A. You can have more than one Cp
B. The cp could have only one activity
C. The cp does not necessarily need to include the activity with the longest duration, if another path contains say three or four activities, and their combined duration is greater than the single biggest, then the single biggest would not necessarily be on the cp.
D. If you have two critical paths, reducing the time of only only activity will not always reduce the minimum completion time, as the other cp would not be affected.

[Scrono13]

Hey Zeus!
I chucked that answer up there. Here's why.
As it was just mentioned, the r values has to be less than -1. For option A, the graph shows that r = -1.
The only other graph that properly shows a geometric sequence with gradient of r < -1 is B.
If it was r < 0, then both A and B are fine. But r < -1.
Sub in some values! You'll see what I mean.

Hope this helps!

How does A show r=-1?
If r=-1, the term number would just alternate negative and positive, but be the same. Say I made a=-2 (a<0), if r=-1, t1=-2, t2=2, t3=-2, t4=2 etc

For example, I said for mine, a=-1 (as a<0) and said r=-2 (r<-1)
From graph A, you could see t1=-1, t2=2, t3=-4 as the y coordinate is increasing each time with graph a?

[Daniel55555555]

Can u tell me why Q7 is E not A

[Dan1995]

Can u tell me why Q7 is E not A

What module?

[Daniel55555555]

Network

[Dan1995]

Network

Because you can rearrange networks, they are not fixed. By rearranging the edges and vertices, they can all be redrawn as planar graphs.

[Daniel55555555]

Planar tree have no crossing edges

[Dan1995]

Planar tree have no crossing edges

Yes, and when you redraw them with the vertices and edges rearranged, the edges do not cross

[Lucho23]

How does A show r=-1?
If r=-1, the term number would just alternate negative and positive, but be the same. Say I made a=-2 (a<0), if r=-1, t1=-2, t2=2, t3=-2, t4=2 etc

For example, I said for mine, a=-1 (as a<0) and said r=-2 (r<-1)
From graph A, you could see t1=-1, t2=2, t3=-4 as the y coordinate is increasing each time with graph a?

Ok, yeah, I got my explanation completely wrong
But, it is B! I'll explain why.

Let's take a sequence where a = -1 and r = -2.
The sequence is as follows: -1, 2, -4, 8, -16, 32, -64, 128, -256, 512.
Option B properly shows this (because of its curve). B shows that the initial values will be small in the whole scheme of all 10 values. Then, as n increases, tn becomes larger and larger! Whenever r > 1 or r < -1, remember, the tn values simply get larger and larger forever! (larger, meaning, even in terms of negative numbers).
Option A shows that the tn values will continue to increase and decrease by steady amounts indefinetly. Have a look. Option A makes it look like the sequence is = -1, 2, -4, 6, -8, 10, -12, 14, -16, 18. This isn't correct.

I know this is a very weird and quite basic explanation without much maths behind it, however, do you see my point? Option B shows the tn values will form a curve and as the tn values increase, so too will the differences between successive terms! The differences between successive terms will not remain somewhat constant (like an arithmetic sequence). Option A Looks more like a sequence which is neither arithmetic, nor geometric.

I hope this clears up the confusion!

Please let me know your perception and why you might think I'm wrong

[Gutthi]

Hey how are you? I really need your help and understanding of this:

I'm paranoid that I may have over shaded the boxed for the Multiple Choice Answer sheet. Like, I think I may have gone too much over the boundaries for each box for it to be legible enough for the computer to read.

I would also like to know that if on the Multiple Choice Answer sheet you named your Modules in the boxes, but just in-case forgot to shade in the boxes, what can be done?

How does the computer interpret shaded answers, will it accept answers if the boxes are over shaded? ( this is how I shaded it --> http://postimg.org/image/5cahf0gab/ )

Thank you for help

[LiquidPaperz]

Hey how are you? I really need your help and understanding of this:

I'm paranoid that I may have over shaded the boxed for the Multiple Choice Answer sheet. Like, I think I may have gone too much over the boundaries for each box for it to be legible enough for the computer to read.

I would also like to know that if on the Multiple Choice Answer sheet you named your Modules in the boxes, but just in-case forgot to shade in the boxes, what can be done?

How does the computer interpret shaded answers, will it accept answers if the boxes are over shaded? ( this is how I shaded it --> http://postimg.org/image/5cahf0gab/ )

Thank you for help

dont worry you'll be fine, as long as you didnt go into the other boxes

On another note, i completely misread 2 questions and these are how i lost my 2 marks + that postcode one, i feel really lost at the moment, anyone else have a similar problem and know how to combat this?

i know i should get around 57-60 on extended response (based on average)  but i really think my chance of 45+ is gone?

[plato]

Gutthi - Your over shading should be ok. If over shading touches an adjacent box, then that could be a problem.
if the box to indicate the module that has been answered has not been filled in, I understand the computer will flag this answer sheet to be looked at by a person. if the name of the module is found to be written there, that person will fill out the appropriate box manually and will resubmit the answer sheet to the computer scan. if the module name is also missing then I think they try to contact the student.