Amnesiac's Further Maths Questions.

[Amnesiac]

Ok, so here is my first question as it relates to the 2008 MAV Exam 1 paper.

Question 7 (CORE):

The following set of data is the number of console games owned by twenty Year 8 students.

9 6 10 7 8 15 5 8 9 8
11 8 7 9 12 7 10 9 8 9

Using a suitable test for outliers, the finding is best represented by
A. three outliers of 5, 12 and 15 as they are not within the accepted range of 5.5 to 11.5
B. two outliers of 5 and 15 as they are not within the accepted range of 6 to 12
C. one outlier of 5 as it is not within the accepted range of 5.5 to 15.5
D. one outlier of 15 as it is not within the accepted range of 4.5 to 12.5
E. no outliers as all data values are within the accepted range of 1.5 to 15.5

I have no idea.

[ReVeL]

Ok. First enter all the data in list 1 of your calculater.

Then, go STAT, CALC, 1:1-VAR Stats.

This will give:
Q1 - 7.5
Median - 8.5
Q3 - 9.5

Now, the 'fences' for outliers are given by:

Lower fence: Q1 - (1.5 x IQR)
Upper fence: Q3 + (1.5 x IQR)

Therfore subsitute in values from above to find the fences.

Lower fence = 7.5 - (1.5 x 2) = 4.5
Upper fence = 9.5 + (1.5 x 2) = 12.5

Anything outside this boundary is an outlier.

Looking back through the data, there is one piece of data that is outside this range, the 15.

Hence, the answer is D.

[Noblesse]

Hence, the answer is D.

Did this exam yesterday, agree with (and can confirm ) D.

[jsimmo]

An easier way to work out the answer is to enter all the points into L1 and create a boxplot.

.. then go to Zoom:9 to view it... you will see that there is an asterics* (=outlier) at the far right (use the trace button to determine its value) and hence, you can see that there is only one outlier of 15 (D)

I find this way much easier than using the outlier formulas

[Amnesiac]

Thanks for all the help. It was the only question i didn't understand lol, but now i do.

[Amnesiac]

lol i just marked myself then and got 35/40. Man those MAV exams are difficult.

[ReVeL]

lol i just marked myself then and got 35/40. Man those MAV exams are difficult.

I've found MAV are very hard exams period.

You wouldn't happen to have the any further ones to upload would you? I've only done them in methods. :/

[ilovesuck]

is there a way to show outliers on a boxplot using the ti-89 (as jsimmo suggested)?

[Amnesiac]

Sorry ilovesuck, i have a TI-83 so i can't help you. Revel, i only have the 2008 MAV Exams 1+2 but this thread: http://vcenotes.com/forum/index.php/topic,6215.0.html will direct you to quite a lot of exams (including MAV) that jess posted up.

[Noblesse]

What I really dislike about MAV is not their difficulty, but their vagueness. Seriously, I thought a professional mathematical association would be able to write a easily coherent paper.

[vce01]

good to know that not everyone is finding MAV easy . VCAA ones are about 3290320342x easier in comparison.

[RD]

Phew! I thought I was getting worse and worse in my exam preperation, did a VCAA then got a way worse score on a MAV one, I thought I was going backwards! (went from a 33/40 to like a 23/40) Still hoping for like a 33-35 study score in Further. Looks like its going to be my lowest subject.

[Amnesiac]

Not necessarily RD. I personally find maths difficult, but apt preperation can make you prepared for any question. Just keep revising your mistakes and you'll be fine. After all, further isn't a hard subject, but you can screw up on little things, so that's where preperation comes into it.

As far as MAV exams go, i don't really like them. In fact, i have never really been fond of any trial exams (besides VCAA) because the questions are always vague and either extremely difficult or extremely easy.

[RD]

Not necessarily RD. I personally find maths difficult, but apt preperation can make you prepared for any question. Just keep revising your mistakes and you'll be fine. After all, further isn't a hard subject, but you can screw up on little things, so that's where preperation comes into it.

Yeah the competitive nature of the subject is going to make it really tough for me to get anything over 35. Lets say I get around 29/40 on Multi choice (which is what I've been averaging on practice exams) and around 42/60 on Short Answer. Couple those with my SAC score throughout the year of 84/100 and ranking of around 5-6 in a cohort of 30 (There's a few people below me who are capable of doing far better than I am, and the people ranked above me are mainly year 11s, I got lucky with SACs) Would I be looking at something around 35?

I definitely prepare a bit more for further but I have like 4 exams in 6 days so I have to allocate my time on those other subjects too.

[Noblesse]

I definitely prepare a bit more for further but I have like 4 exams in 6 days so I have to allocate my time on those other subjects too.

Hehe, it's gonna be a fun couple of days