Suggested solutions for Core, Graphs, Networks and Matrices

[rubiks]

the standard deviation better be 2 or im going to die

Same here mate

[_avO]

C, you are given 2 points (8,300) and (10,450), simply find the gradient by doing m(x-x1)=y-y1 and you get 75

For networks, the 8 is 0 however if you trace from the source to sink with 5 it can get there so therefore it still stands

[stephaheaddd]

why is question 7 networks B not C?

[_avO]

You can cut from the 1 instead of the 2 just looks weird

[nbalakers24]

4+2+3+1 =10

[stonecold]

Answer to Core Q3 is B.

Question specifically said to use the rule mentioned.

Say 99.7% of the data is between 174-186

This needs to comprise of 6 regions, 3 each side of the mean.

(186-174)/6

=2

[_avO]

Here's what you can rearrange it to look like and its more logical to make that 10 cut

[Studyinghard]

Answer to Core Q3 is B.

Question specifically said to use the rule mentioned.

Say 99.7% of the data is between 174-186

This needs to comprise of 6 regions, 3 each side of the mean.

(186-174)/6

=2

legend

[stonecold]

It is C.

I'll explain why.

#1.    180 degrees is the 'median'.
#2.    Looking at the box plot, it is evident that it is skewed. Positively skewed.
#3.    The 68-95-99.7% rule, is a measure from the 'mean'!
#4.    We are unsure, but can guess the mean. (You could calculate, but it would take time).
#5.    Hence, as you are not sure of the Mean, because it is skewed the median does not equal
        the mean.
#6.    Therefore you use s= range/4  to obtain the standard deviation.

Viola:  Option C is correct.

I wouldnt say its skewed but more approximately symmetric therefore answer is B

I agree.  You needed it treat it as symmetrical...

[johsephhh_]

C, you are given 2 points (8,300) and (10,450), simply find the gradient by doing m(x-x1)=y-y1 and you get 75

For networks, the 8 is 0 however if you trace from the source to sink with 5 it can get there so therefore it still stands

OK sounds correct but my theory is this :
u read the x axis from 2 am as 1 so 8 am becomes 4 and 10pm becomes 5 so its (4, 300) and (5,450) with the gradient being 150?

[_avO]

No, it asks for per HOUR, however the scale is 2 hours so therefore if you were to do that you must go up by 2's hence getting (4,300) (6,450) and still m=75

[johsephhh_]

ah your right

[eadvice]

is core 8 D? for sure

[scatteam_2]

isnt question 6 graphs E?
the feasible region in the upper triangle
so the point 3,4 satisfies that...

[_avO]

After you transpose the equations, you have to switch the inequality (as it is previously -y)