The Student Room Group

S4 Edexcel June 2011

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Reply 20
Original post by mir3a
Ended up firming QM instead =/ I'm relying highly on adjustment as it stands, which is never a good thing! KCL will be one place I'll ring first on results day(god knows if they will have availability though) :tongue:

QM is not bad for maths. My sister went their for English. So if you need to ask questions about the area around the uni etc just pm me.
Reply 21
Original post by anshul95
QM is not bad for maths. My sister went their for English. So if you need to ask questions about the area around the uni etc just pm me.


League tables, entry requirements and availability in Extra say otherwise :tongue:

Thanks a lot for offering help with regards to QM btw :smile:
How are we suppose to find
P(X>=12) for X--B(20,0.36) without direct help of calculator??????
Reply 23
Original post by cazzy-joe
How are we suppose to find
P(X>=12) for X--B(20,0.36) without direct help of calculator??????

what paper is this? I don't think this is correct. Maybe post the full question to check for no mistakes.
Original post by anshul95
what paper is this? I don't think this is correct. Maybe post the full question to check for no mistakes.


it is in s4 textbook chapter 1 exercise 1C I think question 2-3 i dont remember :biggrin::biggrin:

Just curious:smile:
Reply 25
Original post by cazzy-joe
it is in s4 textbook chapter 1 exercise 1C I think question 2-3 i dont remember :biggrin::biggrin:

Just curious:smile:

I wouldn't worry, that would never come in the exam as it isn't at least in the formula book tables.
What exactly is for X--B(n,p)
VarXˉVar\bar{X}??

Is it like this..
VarXˉ=Var[X1+X2+.....+Xnn]Var\bar{X}=Var[\frac{X_1+X_2+.....+X_n}{n}]
=1n2Var[X1+X2+....+Xn]\frac{1}{n^2}Var[X_1+X_2+....+X_n]
=1n2nVar[X]\frac{1}{n^2}nVar[X]
=1n2nnp(1p)\frac{1}{n^2}*n*np(1-p)
=p(1p)p(1-p)

OR simply np(1-p)


In S4 new textbook page 24 example 15 in yellow box on right side, it says Var(X bar)=np(1-p) but in exercise 6F question 6 part b) they clearly dint use np(1-p) to estimate Var(X bar).
Reply 27
Original post by cazzy-joe
What exactly is for X--B(n,p)
VarXˉVar\bar{X}??

Is it like this..
VarXˉ=Var[X1+X2+.....+Xnn]Var\bar{X}=Var[\frac{X_1+X_2+.....+X_n}{n}]
=1n2Var[X1+X2+....+Xn]\frac{1}{n^2}Var[X_1+X_2+....+X_n]
=1n2nVar[X]\frac{1}{n^2}nVar[X]
=1n2nnp(1p)\frac{1}{n^2}*n*np(1-p)
=p(1p)p(1-p)

OR simply np(1-p)


In S4 new textbook page 24 example 15 in yellow box on right side, it says Var(X bar)=np(1-p) but in exercise 6F question 6 part b) they clearly dint use np(1-p) to estimate Var(X bar).

You are correct - they have made a slight mistake on the side of the example. They meant to say E(X)=np Var(X)=np(1-p). Note that the result you obtained above is consistent with the central limit theorem:
[br]σ2n=np(1p)n[br][br]\dfrac{\sigma^2}{n} = \dfrac{np(1-p)}{n}[br]
In 2007 June paper question 6 part a) why didn't they use student's t-dist to find critical region but normal distribution instead???

n=15 isn't large sample size...
Reply 29
Original post by cazzy-joe
In 2007 June paper question 6 part a) why didn't they use student's t-dist to find critical region but normal distribution instead???

n=15 isn't large sample size...

in order to carry out the t test, the population standard deviation must be unknown. You are given the distribution parameters in the question i.e. population standard deviation is known i.e. use z test.
So how are you all doing????

Let's make this thread alive :colone:
Reply 31
IM DOING OKAY
BUT MY COCK HURTS
COS I SUCKED IT TOO MUCH
LOL I'm joking

confidence intervals are a pain in the ass
do we have to remember how to do them off by heart
?
?
?
Reply 32
Original post by anshul96

Original post by anshul96
IM DOING OKAY
BUT MY COCK HURTS
COS I SUCKED IT TOO MUCH
LOL I'm joking

confidence intervals are a pain in the ass
do we have to remember how to do them off by heart
?
?
?


Yh me too, i'm trying to calculate the variable length of my cock using a first order differentiational equation, but my calculator isn't strong enough to calculate numbers that large. Also i think that you can take your text book into the S4 exam. i read online that if you do it and lie to your teacher and say its allowed theyll let you. So **** revision. Im going to go take a nap, herpederpderp
Reply 33
Original post by Amirshareh
Yh me too, i'm trying to calculate the variable length of my cock using a first order differentiational equation, but my calculator isn't strong enough to calculate numbers that large. Also i think that you can take your text book into the S4 exam. i read online that if you do it and lie to your teacher and say its allowed theyll let you. So **** revision. Im going to go take a nap, herpederpderp


HAHAHAHAHA I LIKE, I LIKE
Um..a quick S4 question for you faggots:

10 independent samples of the length of my (hard) cock, in inches, were taken and the following results were obtained:
mean = 150.29, s^2 = 0.0000000000001283

Test, at the 1% significance level, whether or not my cock can impregnate anshul95. State your hypotheses clearly, and please do not cover the paper in your cum because you jizzed at the size of my cock.
Reply 34
Original post by anshul96

Original post by anshul96
HAHAHAHAHA I LIKE, I LIKE
Um..a quick S4 question for you faggots:

10 independent samples of the length of my (hard) cock, in inches, were taken and the following results were obtained:
mean = 150.29, s^2 = 0.0000000000001283

Test, at the 1% significance level, whether or not my cock can impregnate anshul95. State your hypotheses clearly, and please do not cover the paper in your cum because you jizzed at the size of my cock.


Hmm there is a flaw in your equations, you havent taken account of the fact that anshul95 is a one legged hermaphrodite which probably complicates it a little. I think you need to increase the variance of your hypothesis to reach a more chi squared value. of course you could always f test the recursion formulae but then the paired t-test would required a pooled estimate of the variance.
anshul96?????? seriously???
Reply 36
Original post by cazzy-joe

Original post by cazzy-joe
anshul96?????? seriously???


Does he look like a bitch? Of course he is serious.
Reply 37
Calm down children :p:
Reply 38
Find the cube root of this matrix: http://i.imgur.com/RDXi3.gif
It reveals anshul95's true name.
(edited 12 years ago)
Reply 39
For those of you that don't give a ****ting ****, here:
http://i.imgur.com/zX4it.gif
(edited 12 years ago)

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