This discussion is now closed.

Check out other Related discussions

Edexcel A level S2 June 2009

Scroll to see replies

Reply 40

Rei

victoria13

if you give me your email i will send them to you... not to sure how you upload them...

Go to "Manage Attachments" and upload the paper through there?

Reply 41

Waterstorm

KeineHeldenMehr

^^'tis fine.

ok, ermm...

hypothesis question, sometimes, really unsure what probability it's suppose to be:

ok, firstly i know it's a binomial...

with:

H_0: p=0.1

H_1: p< or > 0.1

(not sure on either)

but that isnt the only problem...
the approximation is fine.

N(25, 22.5)

just unsure about the probabilty..
is it P (X<40) or

P(X\leq 40)

or P(X=40) and what indicates this in the quoted question?

I would say it's probabilit of not equal to 0.1 for the alternative. And it's

P(X\geq 40)

cause 40 is bigger than the mean (250 x 0.1)

Reply 42

KeineHeldenMehr

Rei

Hey, does anyone have the Jan09 paper?

http://www.freeexampapers.com/FreeExamPapers.com.php?f=QSBMZXZlbC9NYXRocy9FZGV4Y2VsL1MyL1MyIDIwMDktMDEucGRm

Reply 43

Waterstorm

And you know that the grade boundaries are kinda high for an A, I've seen 3.. 2 were 65 and one was 63.

Reply 44

Rocafella89

can anyone help me.. i havent done core maths in a long time (gap year)

just trying to remember, what are the different ways of solving quadratic equations? because this usually comes up when we need to find the median from a cdf..

quadratic formula is one, completing the sqaure is another and factorising is the third? can anyone link me somewhere or tell me how to do these because ive completeley forgot.. just need refreshing. Cheers.

Reply 45

username233985

ok see if this works...

S2 2009 January.doc47.1KB

S2 2009 January mark scheme.pdf290.7KB

Reply 46

KeineHeldenMehr

Waterstorm

I would say it's probability of not equal to 0.1 for the alternative. And it's

P(X\geq 40)

cause 40 is bigger than the mean (250 x 0.1)

hmm...i thought we only used not equal for two tailed test.

Reply 47

Waterstorm

KeineHeldenMehr

hmm...i thought we only used not equal for two tailed test.

I'm sure it is a two tailed test. It's saying 10% of people can tell the difference, and they got 40/250, and they want to see if that is different to the 10%, there's no direction involved.

Reply 48

KeineHeldenMehr

Ali M

http://www.examsolutions.co.uk/A-Level-maths-tutorials/Edexcel/C1/quadratic_functions/completing_the_square/completing_the_square.php

http://www.examsolutions.co.uk/A-Level-maths-tutorials/Edexcel/C1/quadratic_functions/contents.php

Reply 49

Rei

victoria13

ok see if this works...

Thanks a lot

Reply 50

KeineHeldenMehr

Waterstorm

I'm sure it is a two tailed test. It's saying 10% of people can tell the difference, and they got 40/250, and they want to see if that is different to the 10%, there's no direction involved.

true... i agree with you, mark scheme isnt very convincing due to it being handwritten, however they go with p>0.1, dunno how.

Reply 51

Waterstorm

KeineHeldenMehr

true... i agree with you, mark scheme isnt very convincing due to it being handwritten, however they go with p>0.1, dunno how.

Really? That's kinda weird seeing as they mention nothing about increasing.

Reply 52

Rocafella89

KeineHeldenMehr

thanks alot!

Reply 53

Mother_Russia

Quick question, which I always get wrong. When the question says 'Find the probablity that it is less than 4'. Are you supposed to include 4 (ie. 0,1,2,3,4), or not. Alternatively, what about when it's more than 4?

Reply 54

Waterstorm

Mother_Russia

It's saying less than 4.. so no, don't include 4. Same with 'more than 4'. If it said '4 or less/more', then include it.

Reply 55

Mother_Russia

Waterstorm

It's saying less than 4.. so no, don't include 4. Same with 'more than 4'. If it said '4 or less/more', then include it.

kl thanks!

Reply 56

MadMatt

KeineHeldenMehr

whole bloody week been distracted with BGT, and now the revision will kick in today!!!

haha same as probably everyone else lol

Reply 57

sksflipper

yh "not equal to" is defo for two tailed tests.

you pick greater than or less than depending on whether the result is greater than or less that the probabililty. In this case the probability is 0.1 and the sample gives 40/250 students, which is more than 10%. So you are seeing if the probability has increased or not. The result given 40/250 cant show you that the probability has decreased!

So you check whether getting greater than or equal to 40 out of 250 is a significant result

Does anybody know where i can get a copy of the syllabus?

Reply 58

~charmaine~

Hi does anyone know where to find Jan Jun 03, Jan Jun 02 Question paper and markscheme other than freeexampaper.com? I am trying to download them but I have already waited for half an hour!